Summer pests

Date
Published in
Various local newspapers (UK)
Written by
Kim Wilde

The spring and early summer period is always a very busy time for me. Not only because there is so much to be done in my own garden, but also because this year I have had a great deal of other commitments to fulfil.

In early April my first book 'Gardening with Children' was published. This has given me the opportunity over the last few weeks, whilst promoting my book, to meet so many wonderful people across the country that share my passion for gardening.

During these Garden Centres visits, I have been asked many times by visitors to advise on the control of various pests and diseases. Therefore, I thought this would be a good opportunity to share with you some of the most frequently asked questions and their remedies.

Many gardeners this year have suffered from serious attacks of aphids on their plants. These greenfly or blackfly cluster around new buds, young leaves and stems and if not controlled will cause leaves to distort and weaken. As a result a secondary infection of a sooty black mould may appear.

The first job is to kill the aphids by spraying them with a liquid organic pest killer, available from garden centres. If the sooty black mould does develop, then there is no need to worry as this will wash off in time, but unfortunately it will look unsightly for a while.

Another common problem experienced this year by gardeners, has been 'black spot' on roses. Large black spots develop on the leaves and frequently cause yellowing and early leaf fall. The pathogen over-winters on stems, buds and fallen leaves and it not treated it will seriously affect the health of your rose.

This disease once established is difficult to treat, however you should spray with a general purpose fungicide that is suitable for the control of black spot and repeat again fourteen days later or alternatively prune out the worst infected stems and rake up any fallen leaves, ensuring you dispose of all material immediately.

Powdery mildew is another common disease that affects particularly roses, Apples and clematis. White powdery patches appear on the upper surface of leaves, particularly if the soil is dry. Again, you should spray with a general-purpose fungicide, or prune out very badly infected stems. However, regular watering and the use of a mulch around the plant will help to prevent future infection.

If you have a clematis with stems and leaves that suddenly wilt, collapse and die, then you may have the destructive disease, which is commonly known as 'clematis wilt'. Young plants or large flowered varieties are particularly susceptible.

You should cut out all infected shoots to ground level immediately. New shoots should develop from below ground level and over time will replace the infected stems.

Slugs and snails are always a continual problem for gardeners. Instead of using slug pellets that can be poisonous to birds it is best to try some organic methods of control. Try spreading a layer of sharp, coarse grit around the base of susceptible plants that the pests will not be able to cross.

There are also a number of products on the market that may be suitable for you. These include copper barrier tape, organic garlic barrier and biological nematodes. Sometimes the good old-fashioned beer trap can work best.