GARDENING

T he long, hot, dry summer has left a legacy of tired overwrought plants in our gardens. After recent rain in some areas and the prospect of cooler times ahead, it’s a good time to think about reviving the survivors in your garden.

Symptoms of heat stress in plants include burnt, yellow or shrivelled leaves and shoots, poor flowering, poor fruiting on productive plants, leaf loss and dieback. Some plants may have died. Early signs of autumn tones on deciduous trees is also a sign of drought stress as are pests such as two-spotted mite, which are prevalent this year feeding under the leaves of many plants, turning them silvery and mottled.

To check brown plants for signs of life, cut back a stem to see if there’s green wood inside. Stems that are still flexible may regenerate. If you remain unsure about a plant, water it and wait for signs of regrowth.

REHYDRATING SOIL

Where soil or potting mix has become very dry, it can be hard to wet even after good rain. In some cases, plant roots contract so they are no longer in contact with the surrounding soil and are unable to take up the water.

Use a soil-wetting agent – either mixed in a watering can or applied via a hose-on applicator – to help soils and potting mixes rewet and plants rehydrate. A quick way to rehydrate very dry pots is soaking the entire pot in a bucket or tub of water. Leave it soaking until bubbles stop rising.

To check whether water is penetrating the soil, feel the soil or dig a small hole. If the water is penetrating, the soil should be moist well beneath the surface.

Plant damage can be pruned off by cutting back to just above a node (a junction where the leaves and new shoots appear) to encourage a spurt of new growth. Annuals and perennials that have finished flowering can be cut back hard. Annuals that are looking tired can be removed to make way for new autumn plantings.

Water all pruned and stressed plants with seaweed tonic. Follow the directions on the container for treating stressed plants. But remember, it’s important to not apply fertiliser until there are signs of new growth.

LAWN CARE

In areas that have had good falls of rain, many plants are starting to recover without much help. Lawns in particular should start to re-green although where there’s been a lot of dieback it will be necessary to replant bare spots. Reseed the lawn or to use runners or plugs from areas where the lawn is thriving.

While cool-season lawns have taken a battering from the heat and dryness over summer, many weeds have not. Lawn weeds thrive as they have deep roots and thick leaves and can cope with drought.

Part of helping a lawn to recover is to weed (either by hand or with a herbicide) and also to treat areas where the soil has become compacted. Use a garden fork to push into the soil to make a series of holes across the compacted area. Rock the fork back and forwards to enlarge the holes, then water. Follow up with top dressing to keep the holes open. Fertilise with a complete lawn food if there’s been enough rain to encourage good growth.

Ironically, it is often the heavy rains after a long period of dry that lead to plant deaths. Some plants that have struggled for months without enough water find they can’t cope with wet soils and turn up their toes. The good news is that autumn, which is on the horizon, is a good time to plant a wide range of plants.