Summer can bring heat, hot dry winds and high humidity, which all affect the health and appearance of roses. And if your roses have developed leggy or sparse growth and spindly stems it’s a sign that your roses need a summer prune. Summer pruning roses refreshes and reinvigorates the plants and they will respond in a matter of weeks, putting on new growth, ready for another flush of flowers. In fact, you can time rose re-blooming if you have a special event coming up, as they’ll flower again around 6 – 7 weeks after pruning. Perhaps time your rose pruning so you’ll have beautiful home grown blooms to give your Valentine on February 14th!
Rose pruning is not tricky, just trim off around 30% of the overall growth and also remove any dead or thin stems. You can use hedge shears or a good sharp pair of secateurs. Don’t forget to protect your hands, arms (and face!) from rose thorns with sturdy gloves, long sleeves and glasses.
After pruning, collect up all the fallen leaves and stems, which helps to reduce the incidence of disease, and apply some Yates Thrive® Roses & Flowers Liquid Plant Foodand water in well. It’s a complete and balanced liquid fertiliser that has been boosted with extra flower promoting potassium.
Next, spread a layer of mulch, like sugar cane, lucerne or pea straw around the root zone, which will help keep the soil moist and protect the top soil from the baking sun. Reapply Yates Thriveeach week to encourage healthy new foliage growth and lots of gorgeous flowers.
Controlling mites on roses
Summer is prime time for mites, which are known as red spider or two-spotted mites. They are sap feeding pests that can quickly infest roses and other flowering plants (such as marigolds, pictured right) during hot, dry weather. It’s difficult to see mites with the naked eye, as they are very tiny. It’s easier to see the symptoms, which include yellowing and mottled leaves and when populations are large, mites can create a mass of fine webbing, similar to a spider’s web. Roses infested with mites can really suffer, losing lots of leaves and in severe cases mites can kill bushes.
Roses can be attacked by other pests during summer, particularly if there is any new foliage or flower buds developing. Insects such as aphids, thrips, whitefly and caterpillars can damage leaves, stems and flowers. And diseases like black spot (pictured right), rust and powdery mildew can all affect roses during the warmest months, causing leaves to discolour, distort and fall prematurely from the plant. This weakens the rose and reduces the flower show.