Any evergreen shrub, tree or tall perennial (and that means hedges too) can suffer from wind scorch. But what is it – and how can it be combatted?
We’ve often commented on how a plant’s ability to withstand pests, diseases and other potential problems is dependent upon the health of that plant – many problems can only take hold and do damage to unhealthy or weakened plants. Wind scorch is one such problem.
What is wind scorch?
It’s actually very simple – wind scorch would be more accurately named wind dehydration. As everyone knows, moving air removes moisture and just as a Dyson Blade dries the hands, so the wind will dry a plant’s leaves. This is not a problem providing the plant can replace the lost water through its roots. But if the water is not there, can’t be accessed fast enough or if the roots are waterlogged or damaged by disease and/or insects, then the leaves will stay dry, turn brown from the edges and eventually die.
When does wind scorch strike?
Wind scorch can affect plants during summer droughts but is most prevalent when the cold winter winds whip across the garden and when both waterlogging and frozen ground are most likely – plant roots can’t extract moisture in these conditions. Remember, the wind will also dry the soil and plants still need moisture when summer is over.
Plants at particular risk
▫ Plants growing in containers, especially if the containers are made of a porous material like terracotta. The soil in pots and containers is far more prone to drying out than ground soil.
▫ Large-leaved plants
▫ Those parts of the plant or hedge on the windward side
Given that many a hedge is planted to provide protection from the wind, it’s something of a Catch-22 to have to then protect the hedge itself against the wind. The reality, though, is that unless you are planting in a particularly exposed or windy location, wind scorch is unlikely to strike a healthy, properly watered plant. In adverse locations, there are a few simple preventative measures to take:
1. Mulch in spring and autumn to help retain ground moisture
2. Water during drought in summer AND winter (though not when it is freezing!)
3. Choose the right species – or rather, avoid the few hedging plants unsuited to exposed or extreme conditions. These include: Purple Copper Beech (Fagus sylvatica ‘Purpurea’), Escallonia Macrantha AGM or Griselinia Littoralis. Incidentally, Hornbeam (Carpinus betulus) is quite happy in adverse conditions though, in these circumstances, is less likely to keep its leaves come autumn and winter
4. Group smaller containers together and/or move them to a sheltered position – but check that the protecting wall, shed or tree doesn’t create a wind tunnel
5. Protect prized containers in late autumn with well-secured horticultural fleece or bubble wrap
If wind scorch strikes…
Wait until spring and the first signs of new growth and then cut away any affected foliage and feed the plant with a general purpose fertiliser.
The exception is damaged conifers – the damaged foliage should NOT be cut, pruned or trimmed as conifers rarely regrow from badly damaged shoots.