Summer plant care is just as important as winter plant care and we’ve got all the tools you need here at DeWaldens.
Here’s our happy summer outdoor plant care watering and pruning guide.
Summer Plant Care: Watering Plants
Rainfall, sunshine hours, temperature, wind and humidity all dictate watering frequency and, broadly speaking, plants use more water in the warmer summer months and less in the cooler winter months.
Another general rule of thumb is that less than expected foliage growth or fruit and flower production could well be signs that your plants are thirsty.
Best Time To Water Plants
Water plants in the mornings if you can because as the sun comes up plants wake up too and, just like you and me, they like a wee drink. The foliage and soil surface are also likely to stay drier for longer than if you water in the evening, discouraging beasties, slugs, snails and mildew diseases.
Don’t panic if you’re just not a morning person, because evening watering is okay, as the cooler conditions mean less water is lost to evaporation.
But watering in the heat of the day is a definite no-no because water is lost through evaporation from the surface of the soil and the plants will use water more efficiently if watered in the cooler parts of the day.
How Often Should You Water Your Outdoor Plants?
There’s no blanket rule for how often you should water your outdoor plants in summer because every plant has different needs. Take a container plant for example. In hot sunny weather, it might need watering daily, whereas a mature shrub might only need a drink in extreme drought conditions.
Plants will use more water if it’s poured on them, so you can allow them to dry out a little between each watering. They don't need to be wet all the time.
The bigger the plant and more leaves it has, the more water it is likely to lose and the more nutrients it will need to grow flowers and fruit.
Watering Plants In Pots vs. Watering Plants In Borders
A large plant in a small pot will need more frequent watering than one planted in a border. Potbound plants (that have more roots than compost in the pot) dry out particularly quickly
The roots of border plants are free to grow wherever they can find water and draw moisture from a much larger volume of soil than if the roots are confined to a pot.
Soil Types and Watering
Plants can’t possibly extract every last drop of water from the soil, hence the soil still feeling damp to the touch even though plants may have started to wilt. This tends to happen in clay soil because it holds more water than sandy soil, but plants can extract more water from sand than from clay.
Sandy soil can feel dry even though there may be moisture still available to plant roots. Sandy soils tend to need smaller amounts of more frequent watering than clay.
Adding organic matter will improve its water-holding capacity
Pruning Outdoor Plants In Summer
Removing new summer growth before it turns woody reduces growth-promoting nitrogen, allowing potassium to build up – and more potassium means bigger crops of flowers and fruit. You’ll also maintain an attractive shape to your plants too of course and get more dramatic displays from ornamental plants into the bargain.
Spring-flowering shrubs like Deutzia, Flowering quince, Forsythia, Philadelphus and Lilac flower on stems need to be pruned in summer after flowering. Remove stems killed by frost to encourage strong new growth to grow from low down in the plant. It’s best to leave this until early summer when there’s no risk of frost.
Tender shrubs such as Abutilon outdoor fuchsias, Hibiscus sinosyracus and Romneya can be damaged by late frosts. Pruning after flowering encourages strong new growth that will flower next year. Remove the oldest, woody stems right down to the base. Use secateurs or a pruning saw on thick branches.
For apple, cherry, pear and plum trees, removing soft, new growth will promote fruit formation. Prune new excess growth to create space that will allow more light and air to circulate through the tree. This will help the fruit to ripen. You could use loppers, a pruning saw or long-reach pruners.
Hedges and Topiary
Cut back growth to maintain the shape of hedges and topiary like Beech and hornbeam, Box, Leylandii and Thuia, Privet and Laurel. Clip slow-growing beech, hornbeam or box at the start and end of the summer. Try to trim fast-growing privet every six weeks. You could also use secateurs or topiary shears for small hedges.
Climbers such as Wisteria, Jasmine and Honeysuckle and Campsis need to be pruned in the summer to keep their growth under control to stop them from going rogue.
Prune back trailing stems, leaving just three to four leaves. The stems of climbers such as honeysuckle are short-lived, so prune out some of these older stems to avoid a bare base with flowers only at the top. Then train in new growth to ensure there’s an even spread of flowers. Wisteria requires pruning twice a year, in summer and winter.
Evergreens like Camellia, Caenothus and Rhododendron are tender and should not be pruned too early in the year because stems are vulnerable to frost damage. Early summer is the ideal time to prune them to maintain their shape, control their size and remove any frost-damaged stems. Remove crossing and congested branches and trim back new growth to reshape the plant and cut back any gangly, unproductive stems. Remember to always cut just above a leaf joint or bud.