As we have all been basking in this glorious sunshine our geraniums have been enjoying it too – it’s their perfect weather conditions, hot and dry. Whilst tempting at times to have exclaimed “it’s too hot!” I very much appreciate the burst of warmth because this year we have certainly waited a very, very long time for it. The geraniums have all perked up no end following the long, rainy month of April and are all bursting into bloom and at last we can get everything planted up outside … and our plants as well as us, are hopeful of having a long, warm summer.

I popped round to a neighbour at the weekend to help them with their garden … although I hasten to add they wanted some help with their geraniums and I certainly wasn’t out digging or weeding their garden for them … not in that heat! As we chatted away, a few interesting questions came up as we looked through their collection of geraniums – some were doing very well and looked very happy and sadly some looked like they were struggling somewhat.

My geraniums aren’t looking very well – why?

The first thing to look at is whether it is just a few leaves going yellow or whether the whole plant is looking a bit sick. If it’s just a few leaves and the rest of the plant is looking robust enough then I’d suggest it could be a sudden change in temperature or some other harmless occurrence. At this time of the year when we move plants from greenhouses to outdoors they can have a bit ‘shock’ at the change in temperature and losing a few leaves is nothing to worry about. If the whole plant is looking poorly then the first thing I always do is to get it out of the pot and have a good look at the roots and they tell the whole story as to what is going on with the top of the plant.

  • If the roots are pretty much nonexistent then I’m afraid that would suggest something has got into the soil and eaten the roots and this is most probably vine weevil. Have a look for the grubs although they are not always apparent and nowadays it is not the panic it used to be as there are now treatments available so it’s off to the hardware store to buy a remedy. If there are any healthy bits still on the plant you could nip a cutting and root this but if the whole plant has collapsed then there is little that can be done.
  • If the roots are there in abundance but are brown then the root system has died and the most common cause of this is overwatering. Before you yell “I don’t overwater my geraniums!” please see the question on compost below and see if something in there might be the cause. As before there is little that can be done and again, if there is a suitable part to nip a cutting from that is healthy enough then that’s what I’d do.
  • If the roots all look lovely and white and there are plenty of them then … hooray … we have a chance! If the plant is looking sick but the roots are white then there is something the plant is not happy about, causing it to look not quite right. In this situation I’d follow basic steps and follow my usual line of attack in which I think ‘these plants originate from South Africa so let’s give them the nearest we can to those conditions’ which will give them the best chance of recovery. So I always take as much of the old compost off as I can without disturbing the roots too much – repot and replace the compost with fresh compost, put the plant somewhere very warm and very light, give it a drink so it is moist and not waterlogged and then leave it for a day or two. After that I give it a feed and usually the plant bounces back to life and all is well.

Even when you do manage to get a plant to recover you should always take the opportunity to review your general growing conditions and watering as there might be something in the general care that is slightly amiss. However, don’t get blame yourself when you lose a plant … these things do happen and there is no such thing as 100% success rate – we can only do our best!

Is the compost very important?

Well the straight answer is yes … but that wouldn’t make much of a newsletter so I’ll expand (and as you might have gathered if you read my newsletters regularly … I can rabbit on about geraniums at great length!). Two aspects of compost are important – choosing the right one to start with and changing the compost.

Firstly, I’ll talk about changing the compost as that ties in with the question above about sickly plants. It is always a good idea to replace the compost every year. I know what it’s like – we grow a geranium in a big pot and we bring it out in summer and keep it in the greenhouse or conservatory in winter and we can go on doing this for years on end. Geraniums will grow for years if we keep them out of the frosts. So over time the compost becomes compacted and crushed down and also through the constant watering which is needed to keep the plant alive, the compost tightens down. The root system of the plant needs oxygen flowing freely around it as, like us, they need oxygen and if they are growing in tight, hard compost they will really struggle to get any oxygen at all. So a fresh lot of compost will not only have plenty of nutrition in it, which the plants need, it will also be nice and light and the plants will be able to spread their roots happily.

The choice of compost is very important and you should always go for a general purpose compost – if you have a favourite with a good success rate then I’d always say stick with it. I prefer a peat based compost and that is personal choice but you must avoid bark based compost and coir compost for geraniums as they hold too much moisture. Some years ago at the nursery a compost salesman (I’m sure that wasn’t his job title!) came along and told us of a new compost that had been designed especially for geraniums and that it was cheaper than the one we were using … “yippee” we all exclaimed and set about potting up a test batch of plants into the new compost and then stood back and watched the results. We watched … and watched … and watched … as about half of them keeled over and dropped down dead. Back to the old compost for us! So the lesson for all is that, if you do change your compost then test it on a few plants first! A good test to see if a compost is light enough is to squash a ball of damp compost into your hand in a tight fist – when you open your hand it should fall away freely and not stay in a tight hard ball. Most modern composts don’t need any additional drainage material added as they are designed for general use.

My geraniums are very leggy and getting unsightly – what can I do?

Modern geraniums are bred to be short jointed (that is, the stems don’t grow very long between the nodes) and this means most modern geraniums are short, bushy plants which don’t need much attention. An exhibitor growing for showing will spend a lot of time pinching out the growing tips of his (or her!) plants to make them grow in a compact manner. However older varieties or more mature geraniums, left to their own devices, can just keep on growing upwards and upwards and upwards leaving tall stick like plants with little bushy green bits on the top. And these need sorting! If you aren’t too worried about a show of flowers from the particular plant this summer then you can give it a good chop now – if you are then leave it until later in the summer when the main display is over. Grab a sharp knife and cut it back as much as you like – always cut just above a leaf joint in a straight line and the plant will heal over at this point. By cutting the plant back you are forcing it send out more growing shoots and it will do this from lower down and make a bushier plant – it’s a battle of survival for the geranium and you won’t do it any great harm by cutting it back. I’ve seen plants cut back to only 5 inch sticks and a few weeks later they have started sprouting a whole lot of new, fresh growth and the resulting plant has been superb. But please do this with caution as I’d hate to be the cause of you ruining your display! Try it on one plant and if it works then you can do it on your others late summer.

How can I get more flowers from my geraniums?

If the geraniums are happy in their conditions then they’ll flower away without much attention from you – their best conditions are a warm, light place with good compost and being kept moist and not waterlogged. Pots must have drainage holes in them so that they are not sitting in puddles of water – as before, they need oxygen around their roots and this is why overwatering can kill the plant – the poor thing can’t breathe! (Which is a horrible thought!)? Without any doubt, giving your plant a regular feed of fertiliser will significantly increase the number of flowers you get. My neighbour thought this should be done monthly – “no!” I said “give them a feed every week and watch the results”. The fertiliser contains high potash and this encourages flowers to be produced so pop some feed in once a week and your plants will flower even more. It doesn’t take long to do and the results are well worth the little effort involved. Having gone to all the trouble of planting out a display then it makes sense to get the best show possible from it. The same goes for all your flowering plants and our fertiliser can be used for all your garden plants to get more flowers – all your hardy plants, fuchsias, patio plants, border plants … they’ll all flower more with a weekly feed.

Where is the best position to put geraniums in the garden?

As I’ve said before, geraniums love warm, sunny positions but they are a very tolerant and resistant family of plants and yet will still do very well in more shady parts of the garden – we can’t knock down the garden fence to make sure the light is at maximum levels all day long! Some parts of our gardens are shadier than others so the geraniums can be spread around and will be happy out in the garden with some sun, some shade or in full sun all day long. Some plants flag in the heat but not your geraniums … they love it!

As we head towards the long weekend of the Diamond Jubilee celebrations it’s a great time to get the garden looking its best and to have a review of all our plants to make sure they are happy too! To add last minute plants to your displays and to boost up the show then do visit our website today and have a look at all the special offers we have available for delivery to you soon … there is always room for a few extra plants in the garden and the more plants we have, the more flowers we will have to enjoy all summer long so grab some bargains and pop them in all around the garden. I wish you a very happy celebration weekend!

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