Drought tolerant plants

There are lots of good reasons to grow drought tolerant plants. During hot summers the need for frequent watering is time consuming. Not to mention costly to the environment and your pocket too, should rainfall in your area fail to keep up with demand.

We asked The Sunday Gardener, Carol Bartlett, her advice on drought tolerant plants. Here are some of her all time favourites, some of which positively thrive on neglect…

Why choose drought tolerant plants?

Some areas of the country are significantly drier than others. Parts of the south-east like Essex, Kent and Cambridgeshire receive as little as as 513mm of rainfall per annum. Last year, Bury St Edmunds in Suffolk recorded 49 consecutive days without rain.

London is another area of very low rainfall. The capital gets around 557mm per annum – less than Miami and Florida. In these drier parts of the UK, successful gardening is very much a case of “right plant, right place.”

Water is a precious resource, and going forward we need to continue to find ways to conserve it. Incorporating drought tolerant plants into our gardens is an important step towards helping the environment.

The good news? There are some fantastic drought tolerant plants which rarely get thirsty, require very little time and attention, and bring show-stopping structure, scent and colour to your beds and borders. Here are some of the easiest to grow.

Silver and grey leaved plants

This group includes many of my garden favourites – silver and grey leaved plants look great when planted together. Lavender is particularly suitable for dry ground, and there are many stylish varieties that work well as a low hedge along a path, releasing their scent as you brush past.

The shrub Artemisia has finely divided silver leaves which are also aromatic. The pale silver foliage of Artemisia ‘valerie finnis’ makes a fantastic combination alongside the delicate blue flowers of Nepeta, shown above. 

Perovskia, commonly known as Russian sage, has grey/green leaves and masses of spires of soft blue flowers, which the bees love. It’s a small aromatic shrub that’s easy to grow in dry conditions. Perovskia requires pruning in late April/early May. This is to keep the growth compact, cutting back to a small framework of just a few inches. It’s important not to cut the woody parts which don’t have buds, which is why pruning is often delayed until the buds appear as a guide.

Stachys Byzantina, also known as lambs ears, probably has the softest, most downy, silver leaves of any plant and is totally irresistible to the touch! Spires of grey leaves produce small mauve flowers from late June onwards. These insignificant flowers are a bee magnet – attracting bumble bees and female wool carder bees who harvest hairs from the plant’s leaves to make a nest.

The Salvia family is easy to grow in dry areas and this includes common sage, an attractive, small evergreen shrub useful for culinary purposes. Amongst the more colourful flowering varieties are Salvia x sylvestris ‘Viola Klose’ a strong violet blue; and the popular two-toned Salvia ‘lips collection’ – ‘Amethyst Lips’, ‘Hot Lips’ and ‘Cherry Lips’.

Drought resistant shrubs are a good way to provide structure and all year round interest in your planting scheme. Mediterranean shrubs like Rosemary and Santolina are ideal, as is the sun-loving Cistus which grows wild in many areas of the Med where it bakes happily in the sun. Buddleia is ideal in a dry sunny spot with the added benefit of being attractive to pollinators and butterflies. If you don’t have space for a large shrub, there are now more compact buddleia varieties too.

Drought resistant garden favourites

Creating a drought resistant border doesn’t mean settling for something dull. Amongst the group of drought tolerant plants there are some real show stoppers, such as Agapanthus. The striking blue flowers of agapanthus are always eye catching and combine beautifully with the terracotta shades of Achillea, which are also drought tolerant.

Many of my favourite perennials also happen to prefer dry soil:

• Crocosmia
• Echinacea purpurea (Coneflower)
• Eryngium maritimum (Sea Holly)
• Papaver (and the entire poppy family excluding the Himalayan blue)

Even taller, growing up to around 60cms, and a definite garden favourite is Verbena bonariensis with clusters of tiny purple flowers which are attractive to bees and butterflies. It’s not fully hardy all over the UK, but helpfully self-seeds to create new plants for next year. A mulch will help it through the winter.

This perfect drought tolerant planting combination was spotted in Oxford: Verbena bonariensis, sedum, mauve flowering asters and the grass Pennisetum, all of which will tolerate a prolonged dry spell.

Best drought resistant bedding plants

Late spring is the best time to fill gaps in your borders with bedding plants and brighten up summer containers. Some bedding plants are better suited to drier areas than others, although container plants will always require watering, simply because of the growing environment.

Pelargoniums, also known as geraniums, tolerate a great deal of heat and dust. Think of holidays abroad when you see geraniums tumbling from balconies in the hot Mediterranean sun – they love it! Similarly, Gazania and Mesembryanthemum (Ice Plants) like it hot, dry and sunny, not least because they belong to a group of plants whose flowers close when the sun sets, or on cloudy days. Closing their blooms helps to conserve moisture.

Additional bedding plants for dry containers are Argyranthemum (Marguerite) and Osteospermum, both of which have daisy-like flowers. Nicotiana, dahlia, and the lovely muted tones of salvia ‘seascape’ also make good container plants.

Is it a shrub, or is it ground cover? Vinca major, (also known as periwinkle) with its attractive mauve flowers, is drought tolerant. In this combination periwinkle has been planted with ivy, which is very resistant to drought, to make a container display which will thrive on neglect. Alternatively, the 2019 Chelsea Flower Show’s ‘Plant of the Year’ first prize winner, Sedum ‘Atlantis’ is happy as ground cover and in containers. It’s also very popular with pollinators.

How to look after plants in a drought

Even drought-resistant plants will sometimes show signs of stress, and watering may become necessary.

For more efficient watering, check plants individually by testing the surrounding soil to see how dry it is. Some plants will need more water than others. Always apply water to the roots, and in the evening, when less will evaporate. Finally, applying a mulch also works wonders: it conserves water, reduces weeding and improves the look of borders.

We hope this article has given you plenty of food for thought. For more specific advice, visit our plants for a purpose hub page for clever suggestions to tricky gardening problems.