BRIAN KIDD: Rusty roses? Here's how to stop the rot when it gets hot
My word, you do enjoy growing roses. At our allotment store several people have been buying Epsom salts and rose fertilisers.
At the garden centre I also spied readers with a list of products suggested to control most rose diseases.
Just to recap. Use copper mixture – one tablespoon in two gallons of water when roses are in the shade, followed a fortnight later with Multirose and a fortnight later by Roseclear 2 or 3.
Then start the programme again. This ensures pests and diseases do not become immune to the chemicals. Read the instructions before buying. It’s always best to prevent problems, so, if you have not sprayed roses yet, now’s the time to prevent black spot and mildew.
A pump-up pressure sprayer is an investment because concentrates can be bought and they work out much cheaper than those in ready-to-spray containers. These are so-so at the start, but stop working when the container is two-thirds empty!
In the past 10 years there have been serious outbreaks of another disease called rose rust; a very descriptive name for the disease which covers both surfaces of rose leaves with a rusty-coloured powder.
The same disease appears on fuchsias, but each type of rust only attacks that species. For example, hollyhock rust won’t affect fuchsias or roses.
The interesting thing is that while they only attack that particular species, it’s the weather which causes the problem to be severe. Hot, humid conditions cause rust to spread rapidly. If you see it on hollyhocks, spray roses quickly!
When I was an apprentice we used liver of sulphur, which looks like hard, light green putty. This was bashed with a hammer until it turned to a powder and four ounces were added to two gallons of water to prevent rust. It worked brilliantly but this product, like many others, has been withdrawn.
What do we use now? The best product is Systhane. Read the instructions before you buy, spray now and repeat according to the recommendation on the packaging.
John, from Rowlands Castle, prompted me to write about rose rust, but he also wanted to know how and when to prune and train a rambling rose called New Dawn. This is an old, perfumed, light pink rampant rose which looks great when trained correctly.
The main thick stems are best trained tied into wires fixed 10in apart in hoop shapes, so the tips of the main branches face the ground. This induces young shoots to grow from the main stems and in summer flowers appear in great bunches.
Once the flowers die, cut off all the stems which flowered so new stems form. These can be left to grow or, better still, tied down to form trailers or tied in to form the letter C.
It’s well worth having a go at this because the flowers look stunning when trained well. They are easy to spray too.
THIS WEEK’S TOP TIP
You will have noticed that hedges of all types are growing like mad. Try to cut them before new growth becomes woody. Regular hedge-cutting takes far less time and is far less tiring.
Baby birds have left their nests but check before you clip please.