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Browse all our advice on plant problems
Search our A - Z directory to find out expert advice on all your plant problems.
Many viruses affect Lathyrus spp. (sweet peas) causing streaked flowers, mottled leaves, stunted growth and dead patches on leaves.
Swift moth caterpillars are dirty-white with brown heads. They live in soil and feeding on plant roots and at the base of plant stems which can cause plants to collapse.
Take-all is a fungal disease of lawns, particularly those with a high percentage of fine bentgrasses (Agrostis spp.). It causes brown patches of grass, most often in summer when the turf is under drought stress.
Tar spot is a very conspicuous fungal leaf spot disease of sycamore and some other maples. Whilst the large leaf spots sometimes cause gardeners concern, they actually do very little damage to the tree.
Creeping thistle can quickly spread in grassland areas and borders. Once established, it can be difficult to eradicate permanently. You may find that repeated digging out of roots reduces the problem, but chemical control will provide a quicker solution.
Several species of thrips can cause a mottling on foliage and flowers of a wide range of garden and glasshouse plants.
Western red cedar (Thuja plicata) is a popular conifer, grown most commonly as hedging. Unfortunately, it can sometimes be attacked by Thuja blight, an unsightly disease of the foliage that can cause loss of vigour, particularly on young trees.
There is no standard definition for a toadstool, and no clear distinction between toadstools and mushrooms. Both terms refer to the fruiting bodies produced by fungi. Most of these fungi are harmless or even beneficial to plants, but there are a few that can cause disease problems, such as honey fungus and the fairy ring fungi.
Leaf mould can develop rapidly to cause significant yield loss in greenhouse-grown tomatoes. It is rarely seen on outdoor crops.
Many viruses affect tomatoes causing mosaic patterns on leaves, leaf distortions, stunted growth, bronzing or marbling patterns on the fruit.
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