The basics of good rose care begins when you first buy the rose and plant it. It is from proper planting and good early care that roses grow into healthy long lived plants.
BARE ROOT ROSES – as soon as you get home with your rose, open the plastic bag and remove the rose from the packaging. Place your rose into a bucket of water for 30 minutes to re-hydrate the plant.
POTTED ROSES – Make sure they are not potbound, water them with a liquid seaweed fertiliser as soon as you get them home.
PLANTING POSITION AND PREPARATION – Roses require 5-6 hours of full sun per day for best performance. Roses tolerate a wide range of soil types, but your garden bed must be well drained. If your soil is lacking in quality or drainage, mix a premium potting mix or mulch or your own compost into your soil.
- Dig a hole approx 500 x 500 x 300mm deep.
- Plant your rose paying attention to the main trunk; do not cover the graft or the trunk where branches begin.
- Water in well. If winter rains do not occur, water your rose every two weeks.
- If you are planting a dormant rose, do not feed your rose at this time.
- Feed during early spring with a well balanced slow release fertilizer.
Fertiliser requirement will vary depending on the soil and where you are growing the rose.
- POTS– When growing roses in pots a good balanced slow release fertilizer is needed which covers NPK plus trace elements. Granular foods such as Green Jacket or Osmocote can last up to 9 months when used at the correct rates.
- ROSES IN GARDEN BEDS – Can be fed with a large range of plant foods, depending on the size area you need to feed and cost. The above granular foods are good, but if you have a large garden this can be too expensive. This is where organic foods are used.
Pelletized chook manure, blood and bone, hoof and horn and well aged horse & cow manures are excellent. But remember they usually last about 3-4 months only. These organic foods are much more economical for the home gardener and also encourage worm activity in your soil. Do not place manures up against the truck of your rose, place just around the outer foliage area.
Make sure you mulch your roses for summer to reduce water loss and preventing weeds while adding nutrients. Mulches can be purchased by the bag or truckload at large retail nurseries. Lucerne and Pea-Straw are also effective mulches that breakdown offering some nitrogen to your roses.
Pests and Diseases.
Fungal diseases in roses are due mainly to weather conditions and the variety of rose that you have. Cloudy, wet, humid weather is the precursor for the 3 main funguses to thrive. BLACK SPOT, POWDERY MILDEW and RUST.
The variety of your rose is also important as they can vary in disease resistance from hardly being effected at all ie: the Rugosa family of roses which are very disease hardy roses, to very disease prone most of the year. Most breeders are now aiming for high disease resistance in their breeding programs so hopefully each year roses will become even easier to grow. Your average rose is susceptible occasionally during a year and at other times can be quite free of disease e.g. Iceberg, Grimaldi, Bordure Rose, Guy Savoy are quite hardy.
Make sure your roses are in the correct position to start with – 5 hours of full sun per day, well drained soil and an open position ie: not under trees or up against other shrubs. Treatment of funguses is like treating human diseases in that if you keep treating them with penicillin, the human diseases will become resistant. Plant funguses are the same. Keep using one chemical for a year and you may get no control the following year. I always mix a preventative with a curative chemical, if possible, to broaden the control.
Control of Fungal Diseases in Roses.
- BLACKSPOT – purple blotches on leaves
- POWDERY MILDEW – white powder all over buds & stems
Lime Sulphur in cool weather ie winter only. Baycor in warmer months.
- RUST – orange dots on leaves
Mancozeb and Triforine or Zineb.
- DOWNY MILDEW – Die back. Black stems spreading down from the top.
Ridomil Gold is a good treatment but if the die back goes too far, dig the rose out and burn it so as it does not spread to your other roses.
- MOSAIC – virus yellow flecks or variations in leaves
These plants should also be dug out and burnt, if the yellowing is overtaking the rose.
Insects on Roses.
- APHIDS – small green or light brown bugs usually covering flower buds
- TWO Spotted Mite – sucking insects which live under the leaves, turning them a mottled brown
Winter – Lime Sulphur (kills mite eggs) & Winter Oil
(use separately) to smother any eggs.
Summer – Pyranica will kill the adults. For Biological control, Predator Mites which consume Two Spotted Mites.
Confidor. For biological control, use Dipel. Orthene.
- THRIP– tiny black, thin insects about 1mm long that arrive with the Summer heat.
- SCALE – tiny white shell like insect stuck to the stems and branches of roses.
Non-chemical control can be gained by spraying of winter oil during the winter months. Confidor is a good systemic chemical to also control them.
Roses have been loved and grown by gardeners for thousands of years. Native to most continents of the northern hemisphere (there are none native to the southern hemisphere).
Roses are one of the most diverse plant species. The range of colours and fragrances can be matched by few other species, in growth they can climb, ramble, and be a ground cover, a miniature, and pillar, weeping standard or a shrub. Some can live as long as 200 years.
The Genus “Rosa” is made up of 11 groups of “wild roses” from which there are about 140 species. Three quarters of these are native to Asia, 18 to North America and the rest to Europe and North Africa. Keen gardeners and nurserymen have been breeding from these wild roses, creating thousands of hybrids over many centuries. The main types we sell and grow today are mostly repeat flowering modern roses. Roses hybridized from around 1900, include:
- French Delbard
- English David Austin’s
- Hybrid Teas
- Climbers & Ramblers
- Landscape/Ground Cover Roses
For more information on winter pruning roses, pests and disease on your roses, please check out our ROSE FACT SHEET