Fungus – the bogeyman at this time of the year

Give borders a good weeding before spraying and pick up all the deadleaves.
Give borders a good weeding before spraying and pick up all the deadleaves.
Dahlias - one of the boldest plants you can grow .

GARDENING: Brian Kidd is planning for summer with dahlias

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It’s been a very good year for most plants in the garden. But now the evenings are drawing in, the fungal problems on all kinds of plants will become a nuisance. This week’s article should help you prevent these problems.

Prevention is better than cure so we need to arm ourselves with some fungicides which will help prevent mildew, rust on all kinds of plants and, of course, the dreaded blackspot on roses.

It has become very clear that if the same product is used all through the growing season the diseases become resistant to the single product, so it’s a good idea to ring the changes.

Are you prepared to spray the roses, phlox and Michelmas daisies once a week for the next eight weeks?

I thought not, but just in case you may consider this idea – a well-established programme for preventing these diseases.

Always spray late in the evening when things have quietened down and there is no direct sunshine on the leaves.

Add a measure of Maxicrop Complete garden feed which is made from seaweed. This will feed the plants through the leaves and make the chemical even more effective.

The first product is called Bordeaux mixture.

It’s quite cheap and if applied over the foliage it prevents fungi from entering the leaves because it leaves behind a copper covering which ‘burns’ the spores as they try to enter the plant cells. This is organic and safe to use.

A week later, spray with Systhane, which is the best product available to domestic gardeners because it prevents rust which seems to be getting worse every year.

If there is already rust on the leaves, remove them before spraying with the Systhane.

The following week spray Rose Clear 2 or Dithane 945 or Multirose.

I have given you a choice because it’s very likely you have one of these products in the shed. I am ever mindful that people like to save money.

Cleanliness is very important.

Before spraying, give the border a good weeding and pick up all the dead leaves.

These are often crammed with spores which fly back onto the healthy growth.

Wouldn’t it be good if we could use a vacuum cleaner to do this job?


If there is an embarrassing gap in a border, pop in a pot-grown cosmos. There are lots available at garden centres and cosmea continue to flower until the cold weather arrives.