Follow our tips to keep your geraniums healthy
Image: Geranium ‘Jackpot Mixed’ F1 Hybrid from Thompson & Morgan
Geraniums are extremely tolerant plants and known for being reliable, sturdy growers that perform well with very little attention, which is ideal! However, from time to time problems can crop up and we have put together the following ‘troubleshooting’ section to help you get the very best from your plants. Thankfully there aren’t many pests that are attracted to geraniums and most problems are easily treatable so don’t panic if you encounter any problems – you don’t have to throw your lovely plants away!
Click on the topic below which best describes the problem:
- Holes in geranium leaves
- Small white flies on pelargoniums
- Small green flies on geraniums
- Small black flies on the soil
- Brown patches on the leaves of zonal geraniums
- Brown marks on the backs Ivy Leaved geraniums
- Grey mould on geranium leaves and/or stems
- Geraniums not flowering
- Geraniums not thriving
- Rotted geranium stem
- Lower geranium leaves turning yellow
- Cauliflower-like growth on geranium stem
- Geranium Plant collapses and dies
Holes in geranium or pelargonium leaves
This is usually caused by caterpillars. There is a moth that can appear about August or September that will chew the leaves of the zonals which needs catching in the evenings or eradicating with a systemic insecticide. Geraniums are rarely affected by slugs and snails.
Whitefly on pelargoniums
Whitefly can be a problem with the regal and sometimes the scented pelargoniums, though they do not actually damage the plant. Garden Centres are loaded with insecticides to combat this pest, but it is a case of persevering during the warm weather, as they breed very rapidly. We spend a huge amount of money to keep this pest under control – and it still pops up again! Try using “Provado”, it could help here!
Greenfly on geraniums
Greenfly are more of a problem than Whitefly, as these DO damage the plant as they can distort the leaves and spread quickly. Obtain a ‘systemic spray’ from the hardware shop (systemic just means the spray gets into the plant system and the fly eat the leaves and get the insecticide into them). Spray the whole plant, particularly under the leaves and the compost too. Best to isolate the plant if possible to stop them spreading or spray all plants so they are all protected.
Sciarid flies
These are small black flies which you will see on the surface of the compost, and their larvae can damage the roots. They can thrive in peat composts, but are not normally so active that they kill the plants. Once their life cycle moves on, they disappear, so are only a nuisance for about two months in the year. Drenching with a weak solution of Jeyes Fluid will usually put an end to them. Correct watering – keeping the soil moist but never wet – will help to keep them away.
Pelargonium rust
Pelargonium rust can affect many varieties of geranium and pelargonium.
Image: PlantpathfindCC BY-SA 3.0 via Wikimedia Commons
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Pelargonium rust can affect the zonal varieties, and it is getting everywhere nowadays. It first came into the country in 1964 and has gradually spread from Eastbourne, where it was first detected. It only affects the zonal types, and particularly thrives during a damp summer or autumn. However, it is not “life threatening” to the plants, and luckily it does not seem to infect the plants very rapidly, so simply removing the affected leaves will be a good control. We also advise spraying with a suitable fungicide usually available at Garden Centres.
Make sure you spray the underside of the leaves and the compost too so that all spores are treated. Within a day or two take off the affected leaves and either burn or put into the dustbin – do not put them on the compost heap. We do not recommend destroying your plants, as pelargonium rust is only a fungus, much like grey mould or botrytis, and is now endemic in this country, so any new plants you get will most likely suffer from it sooner or later. Ivy leaf geraniums never have rust, only zonals are ever infected.
Oedema
If you see brown marks on the backs of the leaves of your ivy leaved geraniums, you’re probably seeing a physiological disorder called Oedema, rather than a disease. This often affects the older leaves of ivy or hybrid ivy types and is caused by erratic watering. If the plants have got rather dry and are then watered the stomata on the back of the leaves cannot always cope, and they burst. Afterwards they callous over, so what you see is like a scar.
We suggest removing any leaves that look unsightly – the new leaves that grow will not have it. Be careful to keep the roots of the plants moist at all times, especially at the times of the year when they are growing rapidly and are transpiring a great deal. Moist, but never waterlogged, is the golden rule.
Grey Mould
Grey mould, or botrytis, to give it its proper name, is a nuisance once autumn arrives. Damaged leaves or dying flowers will begin to rot once the cold, damp days arrive, and petals falling onto leaves can cause damage. The answer is threefold. Step one is to make sure there are no damaged leaves or flowers on the plants, the second is to supply adequate ventilation so that there is movement of air, and the third is to visit the Garden Centre to buy a fungicide designed to combat grey mould. Smokes are preferable in a greenhouse, because they do not increase the humidity, but are not practical in a porch or conservatory.
Geranium plants not flowering
If plants are not flowering, check the following:
- What type of geranium is it? Regal and Angels naturally flower for a shorter period than other types.
- Is the plant growing well – bushy, healthy and happy looking?
- What feed is it getting? The best feed to boost flowering is high potash – tomato feed is good for encouraging flowering.
- Light – the better the light, the more geraniums will flower.
- Watering – is the plant getting enough to drink? The soil should moist at all times but never leave the plant sitting in puddles of water!
- What size pot is it in? – if the plant is in a huge pot it will be filling the pot with roots and not be concentrating on flowering. Try reducing the pot size – this restricts the roots so plant put its effort into flowering.
Geranium plants not thriving
If your geraniums and pelargoniums are not thriving, check the following:
- Have a look at the roots – Take the plant out of the pot and have a look at the roots. If they’re white then all is healthy and fine. If browning then the roots are dying.
- What compost is it growing in? It needs to be in general purpose compost – not bark based or coir as that will hold too much moisture.
- Is the compost stale and compacted? Try replanting into fresh compost.
- What feed is it getting? The best feed for foliage growth is a balanced fertiliser – our geranium fertiliser is good for foliage and flowering.
- Light – the better the light, the more geraniums will thrive.
- Watering – is the plant getting too much water? If the plant is too wet it will ‘drown’ as the roots need to have air around them for the oxygen.
- Look for sciarid fly – if there are small black flies on the surface of the compost, their larvae may be damaging the roots. They can thrive in peat composts, but are not normally so active that they kill the plants. Once their life cycle moves on, they disappear, so are only a nuisance for about two months in the year. Drenching with a weak solution of Jeyes Fluid will usually put an end to them. Correct watering – keeping the soil moist but never wet – will help to keep them away.
Stem rot
Geraniums are prone to stem rot, and we find that it is more likely to happen in very hot weather. It’s caused by a soil-borne fungus, and if the plant’s container gets hot, it seems to give rise to the trouble. From our experience, it also seems to occur if the plant has dried out too much, and is then copiously watered.
Yellowing geraniums
If you spot yellowing of the bottom leaves of your geranium plants this can occur for any of several reasons:
- Insufficient light is reaching the lower part of the plant. This is probably the cause of the problem if the plants are too close together, or are too far from a good source of light. If you use a photographer’s light meter, you will discover that being three feet in from a window will reduce the light level by 50%!
- The plants are receiving insufficient water at the roots. Although all of the pelargonium family will rot in a humid atmosphere, it is a mistake to think that they need to be kept dry at the roots. They are never dormant, so require moisture all the year round to transpire, but less, of course, in winter and in dull weather. When bone dry the stems go hard and woody, and the plant never grows as well – it is always best to renew the plant with fresh cuttings when this has occurred.
- The plants are drowning! Too much water will exclude the oxygen from the roots, causing them to die. It is said that 90% of house plants are killed from over watering. Never be afraid of taking a plant out of it’s pot to see what is happening to the roots. Sometimes it is possible to take a cutting off the top of a plant if it is only rotting at the bottom.
- The plants have been moved recently and are adjusting to their new environment.
Leafy gall
This is a strange, cauliflower-like growth that occurs where the stem enters the soil, and can occur on any of the pelargonium family. This problem is a complete mystery, as nobody has yet found the cause, so therefore there is no cure. It occurs completely indiscriminately – the first time we found it, in our early days of growing pelargoniums, we rushed off to a nurseryman and said “Look what we’ve found!” “Oh yes,” he said, “I just break that off and throw it away.” And this is still the only thing one can do. The plants continue to grow quite normally once it is removed, and cuttings taken from those plants do not necessarily have it – it just occurs as and when it feels like it!
Geranium plant collapse
Sometimes geranium plants suddenly collapse and die. This is know an ‘Plant collapse’ and has two main causes:
- Vine weevil. This is a pest which seems to be on the increase and is difficult to eradicate. We know that fuchsia growers also are very concerned about it. A garden centre is the place to go to for advice on suitable chemicals to combat the pest. We think they will probably recommend a product from PBI called “Provado”, but they might have other suggestions. We know of one nurseryman who recommends letting bantam chickens loose in the greenhouse! Levingtons do now produce a compost that will kill vine weevil, but that would entail washing the roots and repotting everything. We are sorry there is no magic remedy to this problem.
- Mice! We once had a letter from a frantic customer who said her plants in the conservatory were keeling over from above the soil level. In fear and trepidation, in case we upset her, we phoned and suggested she might have mice in the conservatory. “Do you know! I think you might be right!” she said. Phew!
We hope this advice and guidance is helpful. For even more information about geranium growing and care, visit our geraniums hub page for a wealth of helpful advice.
I have four pots of beautiful geraniums. They bloomed all through the sommer and now, that it is getting cold outside I brought the pots into the house by a sunny window. I sprayed all of them with bug spray before I brought them in. Within 2 weeks many leaves look like lace and huge parts of the leaves are gone. I have looked and looked, I can see no bugs, no residue of a cater pillar, nothing on the leaves or under the leaves. Nothing moving in the pots. What could it be??
Hello Dagmar – this sounds very much like caterpillars – but I’m not sure which! Depends on whether you live in the UK. Also people get pelargoniums (tender plants) confused with geraniums (hardy perennials). I presume you are talking about pelargoniums as you mention bringing them inside.
A few years ago I purchase a weekender on Phillip Island which had a small garden which I’ve enlarged and brought in some of my own favourite plants. There was a existing geranium with beautiful large red flowers which I pruned back quite hard last year. After being always from the island for 4 months due to Covid lockdown I’ve seen that the plant has grown back well but with what appears to be stunted flower heads but minus any coloured petals. Can I send you a photo?
Kind regards, John
Hello John. I’m afraid that you can’t send a photo. It sounds as though it may be a bacterial or viral disease which is stunting your flowers, such diseases can enter through pruning cuts, although I would expect the foliage to be stunted and unhealthy too. Alternatively – if you overfeed with nitrogenous fertiliser that can impair flowering at the expense of foliage.
Hi I have moved from very Wet Wales where I always had gernaiums in pots and hanging baskets and watered daily to a very hot and dry Southern Spain. I was so looking forward to a great show of geraniums and took copious cuttings, grew them on fine and then planted out alongside some prior exsisting ones. They did well, though I was told not to water daily as I had in the UK. Now I note holes in the stems of some of the plants, and with others what looks like step rot- what have I done wrong here,,, should I cut off the rotted stems or are all a dead loss. many thanks Garry
It’s hard to say without seeing them, but if you are able to remove the damaged plant material then its worth a try to save them. I would think that they would benefit from improved ventilation (don’t crowd them too closely together) and consistent watering so that they are not being stressed by too much water followed by too little water. Review their growing conditions and try to reduce any potential stresses upon the plants while they attempt a recovery.
Hi Sue, thank you for your reply,, I will see what happens to them. I have removed most of the offending parts,, it does look as if new leaves are forming- so fingers crossed.
Geraniums leaf tips look like they were dipped in glitter
My geranium bloom stem are swollen, many are split open and the stems are now the pale yellow. This is only on the bloom stem. There are no signs of aphids, caterpillars, etc., but something is clearly wrong. I am hoping you can send advice. Thank you!
I have brought geraniums indoors successfully for several years. They get lots of sun and look beautiful during the cold winter months in Massachusetts. In early spring I take many cuttings for the next summer.
This year I am experiencing black tiny droppings (not bugs) from the plants I just brought indoors. The droppings actually stick to the floor and make a mess! Can you help with what the black droppings are?
Hello Sheila – It sounds as though you may have Geranium budworms but I am not familiar with this pest as it does not occur in the U.K. I suggest you look it up on some USA websites for guidance.
I recently bought 10 beautiful hanging geraniums from a reliable local grower. I kept them inside until night temps were above 50 C. All but one are doing well. One has “fuzz” on all the buds. Do you have any idea what this might be and how I can remedy? Thank you.
Hello
It sounds like a fungal disease of some sort. It could be grey mould which tends to occur in humid conditions. The best way to tackle this is to remove infected parts of the plant and dispose of them. Increase ventilation by opening the greenhouse door or spacing the plants out more to allow for more air movement between them.
Hope this helps
Sue
I’m just going to throw them all out..soil and all. I am so upset. I took great care of them. They were stunning until those worms got to them.
Hello I keep getting brown like thick rust spots on back my geraniums and pelogoniums,I pull tge effected leaves off will a rust spray keep them under control.
Hello. Fungal diseases like rust spots are best controlled through good hygiene and ventilation. I would only use an anti-fungicidal spray as a last resort.
Hi, my red geranium over the last month have been blooming pink and smaller. The leaves are a variegated yellow/green rather than plain green and crinkled. They are located on a east facing balcony so mostly shaded. In Melbourne Australia, and summer has been mild. In self-watering pots and recent fertilisation (manure and liquid seaweed). They have been going well in previous two years except when possums get to them.
Hello
It sounds as though they are struggling a bit. Regular feeding is very important if you are to keep them on active growth all year round, but you will need to give them time to respond to any fertiliser that you have given them. Try to get into a routine of feeding them once a month so that they have a continuous supply.
Also Pelargoniums do best with 4-6 hours of sunlight a day so you may want to consider giving them a brighter spot.
Hope this helps
Sue
Thanks Sue,
I gave them a good feed with “blood & bone” pellets, then a regular dose of a seed weed fertiliser. They have responded really well.
A a bit of “poss-off” has kept the Possums and rats away as well.
The neighbours are envious as they ae in a prominent position.
Hopefully they will continue to thrive over our southern winter.
Cheers
Hello. I have just brought in a large pot of geraniums to over-winter in a cool porch. Every day there are 6 – 8 really chunky large caterpillar poos on the shelf under the plant. They are usually dark brown occasionally pink showing that they have been having a go at the flowers as well as the leaves which are looking rather raggedy now. The thing is, every day I give the plants a thorough examination (including the underside of the leaves) and I see no evidence of caterpillars or anything else for that matter! Could there be something that just comes out at night and hides in the soil during daylight?
Hello
Caterpillars are extremely good at camouflaging themselves. Be sure to check the whole porch, as well as just the plant itself. If necessary, a systemic pesticide will help to prevent them increasing in numbers, but I would suggest that you have a really thorough search for the culprits. (Worth lifting the pot as well in case someone is hiding underneath!).
All the best
Sue
I moved to Devon 3 years ago and have always grown trailing geraniums in Wiltshire where I lived before for the last 2 years my trailing plants have been blighted by tiny caterpillars which bore into the flower buds or the stem just below a flower bud cluster leaving my whole display scant of flowers I inspect daily and find some in rolled up leaves and dispose is there anything I can do or use I’ve pretty much decided I won’t grow them next year
Hello Hazel. It sounds as though you are being plagued by Geranium sawfly. Aside from picking off the little caterpillars, which probably isn’t practicable, you could try using an organic contact insecticide, containing pyrethrins. But you will need to spray when you see the caterpillars and apply repeat treatments. You can also find non-organic contact insecticides which don’t break down as quickly in the environment. The next step up is a systemic insecticide but you need to bear in mind that these kill all non-target insects and therefore are not beneficial to the environment.
The other organic method you could try is using nematodes. These are parasitic eelworms which can be used to control a range of pests without the use of chemicals. There are specific nematodes available for caterpillars.
Can you tell me what this is on my Pelargonium please… Very stunted growth in places. I’ve been told of Greening Virus but couldn’t find anything.
It really is impossible to tell without more information I’m afraid. Stunting of growth can be caused by so many different factors!
At first I though my geraniums were suffering with rust as they had the characteristic brown patches underneath and yellow on top. This was in August, I used a fungicide and picked off all the affected leaves. New leaves have grown back but now I’m inclined to think they are being attacked by insects…possibly white fly. (I have photos) The leaves look unsightly, I am though hoping to overwinter them – I normally leave them in a frost free spot outdoors, my question is will these insects die off when it gets cold or would you recommend an insecticide? TIA
Unfortunately you will need to use an insecticide. If you think that they are suffering from a pest then I would advise not bringing them into the greenhouse until you are sure that they are clean again. Otherwise you will end up spreading the problem further still.
All the best
Sue
I have just dug up my Pelargoniums to over-winter as I have done for a number of years. Several have not been doing so well recently and I found large white growths all over the roots. In the worst affected part of the border there were white lumps attached to roots all over the place. Is it fungal? What should I do? I have taken some photos if of any use.
Hello
It’s very hard to say, as there are so many different fungi present in the soil. If your Pelargoniums aren’t looking great anyway then i would suggest taking cuttings at this stage. As soon as the cuttings are rooted, you can ditch the parent plants. Sometimes its better to start from scratch as Pelargoniums will start to look a bit tatty after a few years anyway.
All the best
Sue
I just brought my geraniums inside since it is getting cold. They did great inside last year and I hope they will do the same this year. One of my four plants though, I noticed, has these tiny little bugs weaving in and out of the dirt. They resemble very small millipedes(centipedes?) They are very (shudder) gross. I’ve examined my other three plants and it doesn’t seem like these little wormy thingies are in them. HELP! What are these and what do I do about them??
Hello
I would be inclined to repot this plant. Try to gently shake away any existing soil from the roots and provide fresh, clean compost. It may sulk for a while so give it time to settle into its new pot. I would also suggest that you isolate it from the other plants just in case. This will help to prevent them spreading to the other plants if you do happen to miss any whilst repotting.
Hope that helps
Sue
2 out of 10 of my geranium’s leaves suddenly seem to be fading to a lighter green than the other geraniums.Flowers seem ok for the time being.
Hello
The oldest leaves will gradually deteriorate as they age. if you are noticing this from the younger leaves then you may need to give your plants a feed.
All the best
Sue
My geraniums have some sort of insect damage… evidenced by little holes in the bud…and the blossom within eaten… previous years I noticed some type of tiny grub…what is it and how do I treat for this insect
Hello. It could be Geranium Sawfly. The little grubs will nibble holes in the foliage and buds. Check the plants over regularly and remove any grubs that you see. If the problem is intolerable then you can use a pesticide to kill them. Spray the plants at dusk for the best results. However, if your plants are in flower then this route should be avoided if possible as the pesticide will also harm bees and other insects which may be visiting your plants.
All the best
Sue
Interesting question…and reply. I have had the same problem both this year and also last couple of years – tiny holes in the buds; I’ve come to the conclusion that it might be a geranium budworm. I noticed on another forum that someone else had posted the same problem and the reply was ‘are you in the USA because this isn’t a problem in the UK’ to which the original questioner said ‘I’m in Cambridgeshire’! I’m on Merseyside …but the damage doesn’t seen consistent with sawfly so although I’m no expert I’m assuming we’ve imported Geranium Budworm from the USA along with chlorinated chicken! From US gardening help videos it seems to be a case of keeping an eye open and picking off the caterpillars when they emerge to try to break the lifecycle.
Hi my geraniums have this insects looks like big flies that grab from the leafs , they have no descoloration or whole in the leafs and the blooms are good, but this insects or pest is all over
Sorry – Im afraid I dont know what these might be from your description.
My geranium looked like a mouse had torn the leaves and flowers. I cut the plants back and netted the whole pot. It has occured again with the stems torn off.
Something is eating holes into the leaves of my geraniums and begonias. I’ve inspected them thoroughly and know it is not Caterpillars. I did however find bugs but I’m not sure what they are. I have a photo I can send. Whatever it is has attacked with a vengeance and destruction is unbelievable. One evening they were great and the next thing they were not. Can you please help? Thank you very much!!
Hello! I’ve sent you a private email so that you can send me your photo. It’s always a lot easier to identify pests with an image.
All the best
Sue
I have had a lovely shocking pink zonal geranium out in the garden for about 3 years. Recently I have noticed browny red spots on the underside of the leaves and blemishes on the top. No signs of green or black fly. The leaves are dying. What do you think it is? I have taken a couple of photos but am unsure how to send them to you. Many thanks.
Hello. It’s always hard to tell without a picture, but my best guess from your description would be Pelargonium Rust, which is a fungal infection. Remove the affected foliage and then spray with a fungicide and this should help to clear it. Like most fungal infections, it is present mainly during cool, wet and breezy periods of weather, being spread by wind and water splashes. You can improve ventilation around the plant by giving it plenty of space. Avoid watering over the foliage too.
Hope it recovers for you.
All the best
Sue
Most of the above problems appear to apply to pelargoniums, not geraniums. I have an annual infestation on my Rozanne geranium which very quickly makes all the leaves on a large plant, approximately half metre spread, to look like lace because there are so many tiny holes. I have examined them for caterpillars but have never actually seen one, so could this be something else?
Hello
There are a few possible culprits such as slugs and snails, but the most likely candidate from your description is the larvae of Geranium sawfly. These little green caterpillars nibble small holes all over the foliage. They tend to hatch out in May/ June and again around September. If you see them then pick them off by hand and dispose of them – but you may need to turn to a pesticide to eradicate them completely.
All the best
Sue
My Geraniums are in pots on a balcony facing the sea (Med).Theywere flowering beautifully but the leaves suddenly started sticking together and looking like there i a cobweb and I saw one little green worm and also tiny black dots can you help please
Hello
There are lots of little larvae that will create webs on their host plants but most can be easily eliminated with a blast of pesticide. If you prefer then you could remove them by hand.
All the best
Sue
My geranium leaves and stems are covered in little white fuzzy dots. The plants are not looking healthy. This started at the beginning of summer and has gotten worse. Any idea what is causing this and the remedy? I took a picture but don’t know how to send it to you.
Hi Diana. It’s hard to make a guess without a photo. If you would like to send an image to blog@thompson-morgan.com then I can take a look.
Best wishes
Sue
My Mrs. Pollock geranium has lost all it leaves and blooms.
Hi Kim
Oh dear – that doesn’t sound good. Has it had any obvious signs of pests or diseases? Or maybe its environment has somehow changed. Sudden defoliation is usually a sign of extreme plant stress. Take a close look and see if there are any clues as to what that might be.
Hope you get to the bottom of the problem
Best wishes
Sue
good day
my geraniums boughtblossom so beautiful but now their leaves start to dry and curl up the stems also dry please advice the reason
Hello. Its hard to say without seeing them. I would always suggest discounting any cultural issues first – such as insufficient/ too much water, adverse changes in temperature etc. Don’t be too disheartened if they don’t make it. Overwintering Pelargoniums can be a little tricky. Think of it as an opportunity to try some new varieties – there are so many to choose from!
Sue
what are the tiny dark bugs stuck all over my geranium stems?They already killed one whole plant and i see them now on another one.What are they and how do i get rid of them? please help me save my beautiful plants.
Hi Graham, unsure type of scented geranium, leaves appear to be getting half eaten, with Brown areas, and tiny areas of brownish thinning leaf, also new growth vanishes leaving just stump of stem. No creatures to be seen, roots are white but seem a bit sparse for plant size. Any ideas please?
Greetings, I seem to have a different problem with my geraniums. They are planted in the ground with tan bark around them. The leaves are very crinkly and deformed. Otherwise they flower well. They have had caterpillers but I believe I have sorted that problem out. Could it be the tan bark?
Hi Valerie
Its hard to say without seeing them. It could be a plant response to a virus, or pest damage. Fluctuations in temperature can often cause leaf deformities too. Glad to hear they are flowering well though!
All the best
Sue
What causes enlarged white growth on flower stems?? Young plants….thanks
Hi Kathy – its hard to say without seeing it but I’d guess that it may be some kind of fungal infection perhaps. Young plants can be susceptible to this, particularly if over-watered. Allow the compost to dry out slightly in between waterings to help reduce the risk.
All the best
Sue
Can you tell me what it is that causes a dramatic shortening of stem growth between leaf nodes? Some deficiency perhaps? The Internode length has reduced from inches to millimetres. On some, the nodes are so tightly packed that it is dwarfing the leaves. They seem otherwise ok, in fact they are flowering at an almost shocking rate, but I’d be happier if they’d put that effort into their foliage instead.
Potassium deficiency can cause this in Geraniums resulting in a dwarfed appearance. It also often causes the leaves to curl downwards at the edges. The heavy flowering that you describe is often the result of plant stress. It sounds as though your plant is definitely in need of a little help. Try applying a dose of High Potash fertiliser https://www.thompson-morgan.com/p/chempakreg-high-potash-feed-formula-4/kww2324TM.
You might also want to review the growing conditions. Does it need repotting? If it is extremely potbound then this will also create drought conditions for the plant which can cause growth dificulties, particularly if they are growing in hot, direct sun.
Hope that helps.
All the best
Sue
My usual tactic with our geraniums–they winter in the garage and get scant watering from October through April and do fine. We are in souther RI. We have one large geranium in a pot that wintered and bloomed in my office this year. In early May we put it on the front porch where got about 3-4 hours of sun and it seemed to be flourishing but stopped flowering. Two weeks ago we moved it to a spot where it got about 6 hours of sun. Now the leaves are going limp a few hours after being watered. My husband has been giving it water 2X a day. He says it seems to pick up after it is watered. I have checked for mold, critters, discoloration and have found nothing. I don’t know if it’s over-watered, needs a larger pot or has something else going on. Thanks for your thoughts.
Hi, i have red geraniums potted in big planters in our front porch where they are in sgade till 2:00 pm and after that receive direct sunlight till 8:00 pm…they are flowering extremely well with big clusters of flowers…but recently i noticed that half of the flower clusters looks water soaked. Newly grown are okay but as they age 4-5 days old they develope a water soaked appreance…Is it a kind of dieases or am i overwatering? I water them twice..morning and evening.Please advice.
Hi– the top of the geranium flower opens but buds below don’t open. Can you tell me the cause? THANKS!
They probably just need a bit more time. Not all of the flowers will open at once – its a gradual process.
hi i have a small slug at base of plants that seems to slowly killing them
what can i do to get rid of them please
Hi Thelma
there are a number of both chemical and organic slug pellets available that will kill off these unwanted plant pests. Alternatively, put sharp grit around the base of your plants, or crushed eggshells work well too!
I hope this works well
All the best
Graham
I also have geraniums that are forming flower buds that then come to nothing. It looks remarkably like the problems I had with geranium moth when living in the south of France. Does the moth exist here and could that be the problem?
The flower buds are forming on my geraniums then going brown and dry and not opening at all.
Hi Sue
Sorry to hear of you problems. is it possible that the plants are suffering from a potassium deficiency that might cause the plant to get rid of the buds as they haven’t got the energy to carry them through to fruition?
Try giving them some tomato feed and see if that helps, also allow the plants to dry out before you water them again, if it’s a bit too moist then the flower stems might suffer too.
I hope this helps
All the best
Graham
I’ve have been cultivating one particular Geranium for about 5-6 years, it has always been healthy until now. I recently moved all the plants that I winter indoors back outside, some I repotted into bigger pots but this plant is in a relatively big pot so I left it. All the other plants are happily growing although not necessarily flowering but my prized Geranium is not happy. I have just taken it out of its pot to find several small white grubs (about 5-7mm long) between 2=5 cm down in the compost. I’ve emptied the pot and left the root ball open to the air, thinking of taking all the compost off the roots to repot it.
Hi Julian,
I’d definitely clean off as much compost as possible and re-pot in fresh. The grubs were probably attacking the roots and doing countless damage. Your plant will not be happy for a little while but keep at it – don’t be tempted to over-water it though! Best of luck with it all.
Cheers
Graham
I have geraniums that I winter in my sunroom over the winter. Some of them are 12+ years old and have been doing great. I put them outside a few days ago and after the first night outside, I noticed that some of the leaves have turned white and curled up. Since they are so heavy to move back inside, I covered then with a tarp at night and then have taken the tarp off during the day. The nights here on Cape Cod have dropped into the 40’s with the day’s reaching mid to high 60’s to low 70’s. Is this a case of putting them out too early? Yikes!
Hi Jan,
it does sound like it, but they’re usually fairly tough so keep them protected as you are and they will recover, I’m sure!
All the best
Graham
Hello,
I have geranium that I have in my kitchen. They have not been outside in two years. They are doing very well, they keep blooming. I noticed, today, on one of the plants (I have 4 Geranium) that there was a red dot, it looked like a tiny bug of some kind, on the leaves. I thought it was odd since, like I said, these plants have been inside for two years. The other plants I have around it are aloe vera and two African Violets all indoor plants. What could the red thing be?
Thanks
Hi Linda,
it sounds like it could be Red Spider Mite, they do tend to like plants in greenhouses and indoors too, remove the leaves affected and throw them in the outside bin!
I hope this helps
Graham
I have milky white spots. When you touch the spot on the leaf it turns into a hole. No sign of insects ??
Hi Betty,
it sounds like some kind of fungal problem, a bit of early rust or similar, give the plants a feed to boost them up , remove the leaves with the infection and possibly even try a weak fungicide on them and see what happens – I hope it all turns out well!
All the best
Graham
I have a number of geraniums in pots. They are watered three times a week for ten minutes, by automatic reticulation, as they are around my fruit trees. All develop a brownish, dead area on some leaves, about a third of the leaf, which eventually dies off. Many also eventually develop stems which are dried out and hollow. Apart from this, they flower well and their new growth is healthy! (They are clearly very forgiving of my ignorance in their care!) I am loathe to use chemical in my garden as I have frog breeding ponds. Thank you for your help.
Hi Lynnley,
to be honest, the sparse watering will not be a problem for the geraniums as they’ll happily tolerate dry conditions. I’d definitely suggest giving them a feed though, water on a feed that will soak into the leaves in the evening, so as to prevent sun scorch, any well balanced plant food will be fine for geraniums. Hopefully it will give the plants a bit more strength to grow even stronger!
I hope this helps
All the best
Graham
My indoor geraniums develop spots on the leaves which become holes filled with a l lacey interior which then become complete holes.
It starts in one leaf then spreads to others on the plant/s.
Any ideas please?
Hi John,
it sounds like you’ve got a leaf borer at work, try and remove any damaged leaves at the first sign of trouble. you can also use an insecticide, but please do do carefully – we still have to look after the beneficial insects!
All the best
Graham
I’m so my wit’s end with the tiny white grubs which are damaging my geraniums. Can you help. I’ve tried normal greenfly spray and vine weevil killer but still they are there. I thought the vine weevil stuff had done the trick but no! The grubs are tiny and crawling on surface of the compost.
Hi Liz,
I’m afraid the best course of action is to tip the plant out onto some newspaper, shake off all the compost and then gently wash the roots in some lukewarm water, to make sure there are no eggs stuck anywhere and then repot the geranium in brand new compost. Dispose of the compost with the grubs in by wrapping it up in the newspaper and putting it in the brown bin (if you have one) … don’t compost it yourself or throw it on the garden as you’ll only spread the problem too!
I hope this helps
All the best
Graham
Thanks. I as beginning to think that might be the only answer!
I have recently moved my geraniums indoors and have noticed that the window sill and window (where one leaf was in contact with the glass) has a film of tiny, pin-head sized black ‘blobs’. Some of the leaves are yellowing and are developing holes. Nothing seems to be moving but something seems to be devouring them and perhaps leaving ‘waste’ but I can’t see anything. They were beautifully healthy a short time ago and the flowers don’t seem to be affected, yet.
Hi Gill,
the yellowing could just be natural die back at this time of year as the plant is trying to enter into a dormant stage to have a rest. Where the leaf has come into contact with the glass sounds like a fungus has developed – I would remove all affected leaves and dispose of asap, to see if it slows down the problem. Keep an eye out for any die back on the stems too and cut them away into healthy areas with very clean and sharp secatueurs!
All the best
Graham
Hello
Why do some of my geraniums have very poor root systems
Hi David,
It’s quite possible that the plants put too much energy into producing top growth and not enough into looking after their root systems, phosphorus based feed would help them in that regard although the use of any balanced feed (20:20:20) will help too.
All the best
Graham
Hi,
I have potted up some geraniums and I am storing them in my conservatory,I keep the water to a minimum but I have noticed some little mushrooms growing in the soil.What is happening.?
Hi Joyce,
probably the combination of temperature and humidity (and the time of year) mean that it’s perfect for the mushrooms to grow. Remove them carefully – gloves and minimal disturbance to them – and dispose of them so that they can produce more spores and spread!
All the best
Graham
Something is eating the buds on one of my geraniums. I cannot see any insects. can you suggest any remedy?
Thanks
Hi Gay,
it could be a small caterpillar that then hides under leaves and is very well camouflaged, have a close look and hopefully you’ll find the culprit!
All the best
Graham
Hi, Graham
I looked with magnifying glass and found no critters on undersides of leaves. I sprayed a couple times with soapy water and that seems to do the trick at least for now. maybe it discourages snails or earwigs. Who knows?
Cheers and thanks for your quick response.
Gay
My Geraniums are very healthy looking but as soon as a blossoms form they die. Have 15 3 in a pot and they are all doing the same. Can you advise me??
Hello
That sounds very frustrating! Pelargonium flowers do sometimes rot off and this is generally associated with growing conditions. They enjoy warm temperatures and soils which are damp but never cold and wet. I suspect that this may be part of the issue. We have had quite a cold spring and if they have had a little too much water then this might not suit them very well. Allow the compost to dry out slightly, especially while temperatures are still a cool. Snip off the failed flowers as this will encourage the plants to keep producing new blooms. I think that you will find that as the summer progresses then they will probably start flowering normally.
Hope this helps you
All the best
Sue
I have now found dozens of caterpillars under the leaves of my geraniums making holes. There are 2 sorts, one green, one black. I believe they come from Moths? Can you verify for me please?
Thank you
Heather
Hi Heather, it does sound like these could be the caterpillars of Winter Moths, pick them off(or the whole leaf that they’re on) and dispose of accordingly!
All the best
Graham
My geraniums have brown spots on the back of the leaves,they are flowering well.
All my geraniums are suddenly dying.After being very prolific ,now when I deadhead the top of plant,instead of being green with new shoots are now brown and dead looking.Inhave watered and fed regularly and the problem is all around my garden in around 20/30 pots.Any idea what has caused this?
Hi Roger,
we suspect that the plants have become over wet – possibly through the deluges we have had recently. Are the stalks wet and mushy? The only chance you have is to raise the pots to allow them to drain almost completely – leave the compost until it is barely damp, and them maintain that moisture level until the plants recover. Unfortunately, if the plants have been prolific up to now then there will be an awful lot of young, soft growth, which can be prone to bacterial stem-rot. I hope that they do recover, fingers crossed!
All the best
Graham
hi i have 3 hanging baskets with geraniums in 2 are ok but the other is getting decimated by something,eating all leaves an tops off the storks of flower, have checked 4 caterpillars but cant see any, did see an kill a little brown grub. do u think spraying with washing up liquid will help or can u advise on something else. cheers
Hi Boyce,
spraying with very very diluted soapy water might well help, failing that an insectacide, although please be careful when using as we don’t want to affect any other insects – It might pay to “quarantine” the plant for a short while while you treat it.
I hope this helps
Graham
Hi
I live in Spain and have holes in the stems when i break open they are grubs inside. One plant in a pot has nearly been completely eaten. Now there are lots big fat grums left in the earth.
Hi Jan,
Borers can be a real nuisance on many plants unfortunately. The best way to get rid of them is to use a pesticide, obviously very carefully to avoid hurting beneficial insects. Keep an eye out for eggs on the undersides of leaves too, these can then be removes to help prevent further problems!
I hope this helps
Graham
How do i solve the problem of black bore holes in the stems of otherwise healthy geranium plants?
Hi Jane,
Borers can be a real nuisance on many plants unfortunately. The best way to get rid of them is to use a pesticide, obviously very carefully to avoid hurting beneficial insects. Keep an eye out for eggs on the undersides of leaves too, these can then be removes to help prevent further problems!
I hope this helps
Graham
Some of my geraniums accumulate a very small, black granular/tubular type of substance on the leaves. I notice it about every 2-3 days. I just flick the leaves and it fall/rolls off the leaves. These geraniums tended to having yellowish leaves when I got them and no matter how much you pick off the yellow leaves, they continue to turn yellow. What do you think is going on? Thank you,
Hi Pam,
the yellowing of the leaves sounds like the plants are lacking in nutrients slightly. I would suggest a fully balances liquid feed, with trace elements such as magnesium in it too, this will help the leafy growth to come back and also improve the colour too!
I hope this help
Graham
I recently purchased a Crocodile Ivy leaf geranium. I am continually having to cut the leaves off as they turn a tan/brown color. What is causing this?
Hi Donna,
is it possible that the plants are getting too much water? this is quite common with geraniums of all types. also a lack of nitrogen in the soil will cause poor leaf growth too. a balanced feed will help out in both cases.
All the best
Graham
I have a tiny caterpillar on the underside of leaves, it appears to have tine yellow mrkings, it is slowly eating my geranium and begonias I find them on the underside of leaves I am not sure how to deal with them, I have always shied away from insecticides because of the bees any advice please I am not sure what these are.
Hi Lucy, is there any chance you could send me a photograph of the offending caterpillar and we can take a look for you!? e-mail me direct at gward@thompson-morgan.com
Many thanks
Graham
I have several containers with Geraniums and all are thriving apart from one. Out if five plants in the container only one is thriving, two have completely disappeared! We had been away and this happened while we weren’t there. When I came to investigate I found that the tub has hundreds of what look like yellow ants or spiders. I have bought more plants but am nervous of planting them in case these insects eat them. I’m not a very experienced gardener so am at a loss. What is your advice? Thanks in anticipation
Hi Judith , is there any chance you could send me a photograph of the offending bugs and we can take a look for you!? e-mail me direct at gward@thompson-morgan.com
My Geraniums have what looks like white powderlike areas on the top of the leaves. These areas wipe off easily. Any idea?
Hi Sharon, is it from evaporation of water, possibly with liquid feed in it? , leaving a residue on the leaves? It’s a common question we get here when plants are sent out as we often see marks on the leaves that will wipe off that are exactly that.
I hope this helps
Graham
When I break off the dead flowers, little dry “clouds” puff up from the geranium?! I’m afraid it might be some kind of mould that’s dried out and becomes airborne? The weather’s been wet; but the geraniums are otherwise flourishing.
Hi Val, it’s probably the dust form the deaf lowers, or old pollen etc, as long as the leaves etc on the leaves look healthy then it’s probably nothing to worry about.
I hope this helps
Graham
Why are my plants going purple on my balcony? Geraniums money plant
Hi Christine, this will be because the cooler temperatures at night are meaning that the plants are not yet fully active and suffering a lit bit from phosphorus deficiency as a result of that. When we get more constant temperatures, the plants will perk up, give them a fully balanced feed for now to help them along.
I hope this helps
I have white like spots on the tops of the leaves.cannot see any black fly or green fly.what could it be.have just planted them out into runs.
Hi Susan, are they on the leaves (so that they wipe off) or are they actual blemishes in the leaves themselves?
I have something similar to this I think. It’s as if the top layer of the leaf has been removed, and sometimes underneath too so that it looks like a bit of nearly transparent leaf. Then the leaf gradually curls and goes soft and dies. At first I thought it was spots where they had been watered and been burned through the conservatory glass but now I don’t think so.
I’d like help too please.
It sounds like you might have a tiny bug called a “leaf miner” there Ann, they burrow into the leave and actually eat the flesh of it between the top and bottom layer, making the leaf look transparent, which eventually dies, try a general purpose bug spray, or keep an eye out for early signs and pick the little blighters off!
Thank you for your prompt reply. I have been picking off the diseased leaves and shall watch out for new infections and hopefully get rid of them – before there are no leaves left!