Distressing sight of plants hit by drought
One of the saddest sights in gardening is that of otherwise healthy, cultivated plants collapsing through lack of water, and this is the time of year it happens.
A sequence of hot, sunny days assisted by a drying wind, can put garden plants both new and old under severe stress, more so when moisture lost through their leaves (transpiration) far exceeds the amount a dry soil or compost can offer as replacement.
In such conditions recently planted annuals and herbaceous perennials will wilt and die without immediate action.
Some deciduous woody perennials handle the situation by shedding their leaves to arrest water-loss and increase the chance of survival.
Our winter cherry (Prunus autumnalis ‘Rosea’) has a trunk circumference of one metre plus, and never fails to entertain from November until April. However, on two drought-ridden occasions over the past decade, no sooner have the new spring leaves appeared than the tree has cast them all.
A mature holly tree nearby has gone through the same process, losing one third of its canopy. In both cases it’s happened after a long period without rain. However, copious watering has saved the day.
Whether the roots of our plants are confined within a container or allowed a free-run in garden soil, the planting process and subsequent watering, are key issues.
Hardy plants we purchase are often pot-bound, the roots spiralling in a tight circle which can be difficult to tease apart by hand – but it must be done to encourage development and foraging for water and nutrients. Whenever I’m asked to check specimens planted in autumn that have failed to initiate growth the following year, digging them up most often reveals the unbroken root-ring.
There are several routes to success in gardening and if a particular method works for you – stick with it.
For example, with everything I plant, from a jumbo vegetable or bedding plug to a standard tree, the hole receives water before the subject is introduced. This way, moisture surrounds the roots immediately. Some of the planting demonstrations I see on screen introduce the plant, backfill the hole, make the soil firm, then water. If this happens during a hot period when the soil is dry, some moisture will be lost to evaporation before it reaches the roots.