Get a little expert help with your pour decisions
As the mercury rises, which garden plants should we be prioritising and are there some we shouldn’t worry about watering? Hannah Stephenson finds out
As the heat of summer continues, many gardeners have become a slave to the watering can and hosepipe.
But will some plants take more drought than others? Will vegetables wither with little water, and what about our beloved borders and cherished containers?
RHS chief horticulturist Guy Barter offers some tips on how to prioritise your watering regime, especially if you are short on time...
1. Pots and hanging baskets
These should be your first priority, says Guy. And the smaller the pot, the more it’s going to need watering, because less compost means less moisture is retained.
“Pots naturally restrict the root volume, so need to be watered every day,” he says. However, some plants will tolerate dry pots, including pelargoniums and lavender, so consider Mediterranean droughtlovers if you don’t want to be watering too often.
During really hot spells, you may also benefit from placing pots together in a shadier, sheltered spot out of the wind. The collection will create its own little micro-climate and there will be less evaporation, Guy notes.
“Place your pots into saucers to catch the overflow,” he adds. “The pot will suck the water back up. It’s also worth considering selfwatering pots with a built-in reservoir of water, which can be very effective.”
2. New plants
If you have new plants, which you have just planted out – whether seedlings, annuals, perennials, edibles, shrubs or trees – they will need watering while roots develop.
“Newly planted things need watering every day to start with, and then every three days and five days when they gradually root out and start growing. This is for any plant you have planted since April, and don’t forget things you planted last winter or the winter before,” says Guy. “Trees and shrubs take a while to get going. After two years, they will probably be ok. With newly
planted trees and shrubs, they will need a good soak every 10 days to wet the roots. After a couple of years, they can look after themselves.”
Even drought-tolerant herbs such as sage, rosemary and thyme will still need watering for a few weeks if you plant them now, he says.
3. Perennial borders
“The watering regime very much depends on what perennials you have in your border. Some are very drought-resistant, such as lupins, stachys and Phlomis russeliana (Turkish sage). Often, there’s no need to water them at all,” says Guy. “Other plants tend to come from prairie regions, like rudbeckias and echinaceas and phlox. These are regions that have summer rainfall, so they are not that tolerant of drought, particularly on sandy soils which don’t hold a lot of water, and clay soils where the plants can’t access water. Watering every 14 days may be enough, but it’s got to be the right kind of watering.”
4. Vegetables
“I would water the area well before sowing seeds, letting it drain overnight. For transplants, I would water every couple of days until they get growing. When that happens you can water once a week,” says Guy.
“For crops – and you must remember that vegetables are mostly water so they do need watering – give them a really good soak every 10-14 days that completely wets the ground, and check with a trowel a couple of hours after watering, to make sure it’s gone down where the roots are.”
5.
“Things like camellias and hydrangeas are intolerant of drought, so plant them in a bit of shade,” Guy advises.