I promised to advise you on the treatment of roses in order to prevent pests and diseases.
I know from your letters how important roses are and I will start with a letter from Gill, of Waterlooville, who tells me she has moved and in the new garden there are wonderful old roses which have tall brown stems with leaves at the top. Gill is reluctant to prune them hard in case they die.
Try this. Buy a bottle of Maxicrop Complete liquid fertiliser and dilute it to the strongest recommended feed for mature plants. Give each bush two pints applied slowly. Make up another batch and, using a pump-up sprayer, spray the brown stems every other day for a fortnight.
Sounds stupid, but epicormic buds will break out on the old stems. These will produce shoots and after flowering the brown stems can be pruned down to the lowest shoots.
Pests and diseases become immune to the sprays we use in the garden, but if we use a selection of different sprays we can prevent this immunity.
If you prefer organic remedies, sulphur and Bordeaux Mixture are good to prevent diseases. Soft soap is useful to keep pests under control. You’ll find these at your garden centre. As ever, take your specs.
I regularly recommend Maxicrop Complete liquid fertiliser. This is also organic because it is made from seaweed.
When using the spraying programme recommended, add a measure of Maxicrop in the sprayer. It helps spread the fungicide. Once the foliage is well-established, in fact right now, apply the first spray using Bordeaux mixture. A fortnight later, spray with Multirose. This will smother black spot and mildew spores and kill pests too. A fortnight later, spray again using Roseclear or Systhane, both excellent fungicides.
Two weeks later use the Bordeaux Mixture followed by the other sprays and continue this all through the autumn. Your roses will be free of pests and diseases and you will have worked hard to achieve this. You deserve great results and in addition to all this, the leaves will be healthy and glossy because of the Maxicrop.
Once the first flush of flowers fades, the blooms are cut off down to a bud or shoot just below the tip of each branch.This is far better than pulling off the dead flowers and throwing the petals on the ground. Don’t do this because the dead petals cause black spot, mildew and rust. Put them on the compost heap.
After dead-heading, fork over the soil to three inches and apply 4oz per square yard of Vitax Q4 pelleted fertiliser. Perfect results.