Advice
RHS Help & Advice
Weedkiller damage
Weedkiller damage can occur in various ways: from drift when spray is applied during windy or warm, sunny conditions; using a poorly rinsed sprayer or contaminated watering can or by mulching with recently treated mowings.
Symptoms
Hormone or growth-regulating weedkillers (such as 2,4-D from lawn weedkillers) cause narrowing of leaves with parallel veins, twisting or distorted leaf stalks in various plants, adventitious roots and swollen stems in brassicas, and hollow tomatoes. Tomato plants are very susceptible to hormone weedkiller damage.
Damaged vegetables
Beans, carrots, lettuce, peas and tomatoes can still be eaten. Brassicas (except sprouts) do not usually recover and should be destroyed.
Other
symptoms
Roses and raspberries are particularly sensitive to glyphosate from July onwards. It causes stunting and leaf malformation, which may not be evident until the following season. Weedkillers formulated for controlling weeds on paths or drives tend to have residual properties, remaining in the soil for weeks or months. Those based on sodium chlorate can leach into neighbouring beds or cause damage to lawns adjacent to treated areas. The roots of pathside shrubs may extend under the path or drive and damage can be occasionally encountered when the application rate has been exceeded, or on light, sandy soils, low in organic matter where the weedkiller has penetrated deeper. Yellow or chlorotic bulb foliage can indicate accidental spraying with a weedkiller containing diquat the previous season.
Further information
A conservation and environment leafet on the use of garden chemicals is available.