Rose guru Ludwig Taschner’s inbox always overflows with gardening queries… his answers could help you, too!

Some of my rose bushes have pushed out thick, reddish stems from the base of the plant that look quite different to the other stems. Should I remove them?
These stems are called basal shoots; they are the new stems that usually determine how tall a bush will grow in a season. They should not be confused with suckers, which are thornless, green stems that grow from the rootstock and should be pulled off. Once a basal shoot reaches knee height, pinch off the growing tip; this encourages the stem to become woody, which helps it to withstand strong winds without snapping. Pinching also encourages nicely balanced side stems. If pinching is not done in time and a candelabra type of growth develops, cut out the three centre buds.

How often should I fertilise my roses?
In most areas, roses need fertilising once a month from September to April. Feed with a rose fertiliser (5:1:5 or 8:1:5) in the middle of the month, according to the recommended dosage (giving more than the recommended amount won’t make the roses grow faster but will burn the roots and leaves). Brown, brittle edges around the leaves or black stems are signs of over-fertilising. Fertiliser is best sprinkled over the leaves; this helps to spread it fairly evenly over the root zone. When you water the plant, the water will dissolve the fertiliser and carry it down to the roots. Don’t place fertiliser in heaps or rings around the roses as this concentrates too much fertiliser in a small area and causes scorching.

My rose bush is not growing well and only produces a few short stems with flowers, which is very disappointing. What can I do?
Snip off all the tiny flower buds with at least one leaf. Flower production takes a lot of energy from the roots, so removing these reverses the process and more food is pushed to the roots than is being absorbed. This encourages the formation of hair roots, which absorb more water and nutrients, resulting in more shoots and leaves and eventually strong basal shoots and a renewal of the bush. Also increase watering to at least twice a week.

Ludwig’s tips for September

• Finger-prune hybrid tea, Antico Moderno and Spire Roses to lengthen the flowering period. This involves pinching the tips out of 25% of the developing shoots on a bush with your fingers, which staggers the flowering period, stimulates new basal shoots, encourages root development, and creates more green leaves quickly.
• Increase watering to every second or third day to accommodate the rapid growth.
• Boost new growth by fertilising with a rose fertiliser such as Vigorosa.
• Drench with Koinor in early September to repel insects (especially aphids), thrips and boll worm. For protection against fungal disease, spray with a combination of Ludwig’s Insect Spray, Chronos and Spray Stay or Rose Protector.
• In coastal areas that are still getting rain, prevent black spot by spraying with Chronos or Garden Protector.
• Mulch rose beds with pine needles or peanut shells to keep the soil and roots cool during the heat of the day.

Words and image: Home magazine