[By Ben Swane]
CULTIVATION OF ROSES includes:
- Preparing the Ground
- Pest Control
Added to which are:
- Fertilisation and
- After Care of Roses
Choose an open sunny position, sheltered from high winds. The north easterly aspect is best but provided the area is not ruthlessly exposed the sunnier the better. The site should also allow for adequate drainage through the soil as well as run off in times of excessive rain.
Roses grow best on their own in groups or in specific beds for the purpose. This makes applications of sprays or fertilisers much easier than going from place to place throughout the garden. Limit the size of a rose bed if necessary to allow easy access all round, the plants will benefit but it may mean fewer plants.
This planning will provide plenty of air circulation between each plant to prevent spread of disease and will also allow easy access for picking blooms. Generally, 1m between plants is the desired distance but this may vary according to the size the plant may ultimately achieve. Preparing the site in this manner will allow you to calculate the number of plants required.
Good drainage through the soil is essential for roses. Test by digging a hole about 30cms deep and wide and pour in 4ltrs of water. If water remains in the hole up to one hour later, it means that the soil has a lot of clay and requires concentrated effort to improve it. Incorporate 2kg per square metre of gypsum by digging it to a depth of 20cm.and then follow the directions below.
Dig the overall area of the garden bed to a depth of 20cms incorporating plenty of milled cow manure, well rotted garden compost or leaf mulch and allow to lie fallow for between 4 and 6 weeks prior to planting. In the absence of rain, dampen the ground lightly at least once weekly.
N.B. Do not add LIME together with manure or compost at the same time as roses do not like strongly acid soils. A pH reading between 5.5 – 6 is best.
For most areas of Australia the preferred planting time is the dormant season between June and August. In extremely cold areas planting may be left till later than August but the use of straw to cover the plants will usually provide enough frost protection in this initial stage.
1. Stand the new plants in a bucket of water to soak the roots and clear them of any gel preservative or foreign mud.
2. Have planting holes ready so that the roots of plants are not exposed to strong, drying winds.
3. Check roots and stems for any that are broken or damaged and prune these cleanly back to an undamaged area. Clean secateurs between cuts.
4. Make a small mound of soil in the base of the hole if necessary & spread the ‘crown’ of roots over it.
5. Ensure the bud union of the plant is just above ground level. Place a small stake across the hole and grasp the plant stem against this as a guide. Never place the plant more deeply in the hole than this.
6. As you back-fill the hole with soil add 2 teaspoons only of water storing granules around the roots with the soil. Remember these swell with moisture and will displace soil from the hole if you add more.
7. Break up any large clods of soil before backfilling the hole to the half way point. Water the roots in well and move to the next plant until all are settled in this manner.
8. Continue to back fill the planting holes to the original soil level creating a small wall of soil to form a saucer about 20-30cm in diameter. Apply water slowly to each saucer so it fills and soaks away to the roots.
9. Mulch the surface of the rose bed outside of the saucer to retain moisture in the ground.
10. Water twice weekly until plants begin to shoot into leaf. Further watering instructions come in After Care of Roses.
N.B. When planting standard or weeping tree roses drive the stake into the hole first and plant against this. Driving the stake in after planting may damage the brittle roots. When using an iron pipe and ‘rose ring’ place the ring over the water pipe first and then drive the pipe home. Then raise the ring into position and place the weeping standard rose into position and plant.
Sometimes it is better to prune too much rather than too little! It is important not to be apprehensive about this aspect of rose growing. Roses are tough, forgiving plants and many survive well in spite of savage cut backs!
WINTER PRUNING requires removal of 60% of the bush to open up the centre of the plant and to induce vigorous spring growth. I use the “Push & Cut” method. Remove all old (brown coloured) stems and twiggy or frail stems. Very large, very old stems may require the use of pruning saw for removal.
Unless the plant is a tall variety maintain a uniform size by regular pruning of all the rose plants in the bed.
IMMEDIATELY after winter pruning, gather all leaves and prunings from the ground and spray the plants with LIME SULPHUR.
At this stage the plants should be entirely without leaf but with swelling buds ready for spring growth. Do not use lime sulphur once leaf shoot has occurred.
SUMMER PRUNING requires 40% to invigorate the bush and encourage a strong flush of autumn blooming after summer production ceases or begins to weaken. Favourable weather condtions of sunshine and warmth should see blooms appear within 6-8 weeks.Some winter flowering roses like Lorraine Lee are best pruned in autumn and climber, weeping, miniature and ground cover roses are all best pruned in winter.
a 40% summer-pruned bush
A rose bush summer pruned to 40% of growth. Hybrid tea/floribunda or David Austin
AFTER PRUNING (winter or summer) apply to each rose plant the equivalent of a 10″ size (250mm) bucket of cow manure plus 1/2 kg of Organic Life pellitised manure.
It vastly improves the growth of the plant and encourages more flower production if the blooms are picked regularly. Cut stems as long as possible and as often as blooms are available, allowing 3-5 sets of leaves at the base of the stem to remain on the bush. From these leaf bases come the new stems of flower.
Removing just the dead head of blooms produces long, thin growth and reduces flower production. Even if you don’t hold with picking roses for the vase, pick the spent flower and its stem exactly as you would for ‘Cut Flowers’ above.
For those that flower more than once during a season blooms should be produced every 6-8 weeks from spring through 6-8 months of the year.
I do not recommend digging any rose garden bed.
If it’s very old the addition of plenty of cow manure and organic material such as compost is my highest recommendation. Once this material is applied and lightly scratched into the top 2-5cms of soil, no further cultivation such as digging should be required. Apply a mulch of lucerne hay to a depth between 7 and 10 cms, re-applying this as required during summer. As all mulches break down it is necessary to re-apply to maintain moisture levels in the soil.
Lucerne hay releases calcium and potassium to the soil as well as valuable nitrogen and is instrumental in encouraging earth worms.
Other significant mulches are stable manure (mixture of straw & manure), composted sawdust and wood waste products, grape crushings as used in Mildura, poppy trash (Tasmania), cow peas. All legumes are good although there may be some germination of seed.
Twelve weeks after any winter applications, a complete rose food (chemical) or blood and bone (organic) should be applied. In late summer apply a combination of Nitram or Urea (38% nitrogen) at the rate of 200grams and 150 grams of sulphate of potash per plant to the surface of the mulch or soil and watered in by hand for best results. Water each plant thoroughly after this application.
Some foliar application of seaweed products are effective both from a growth and disease resistance viewpoint.
Black spot is a major rose disease and for control to be effective, spray applications should begin when the first leaves appear in spring, with follow up sprays during summer and autumn. Recommended chemical products are Triforine, Mancozeb Plus and Baycor. It may be necessary to alternate these products if one or either becomes ineffective in control. Organic Control is effective when used as a preventative immediately leaves begin to develop. Mix to a paste 3 teaspoons of bicarbonate of soda and disperse into 4.5 litres of water to which 2.5 tablespoons of PEST OIL has been added. Spray three times within the first two weeks of leaf development and then weekly thereafter. Spray till the plant is dripping with the mixture.
Rust may be controlled with Baycor.
White Rose Scale should be sprayed with lime sulphur in winter and Pest Oil in summer.
Aphid &Thrip (including Western Flower Thrip)
Both aphid and thrip are capable of transmitting diseases to other rose plants. Organic products such as pyrethrum, Baythroid and Confidor are effective for infestations of small number. Large infestations may require the use of stronger chemical sprays such as Folimat, Rogor and Mavrik. Use strictly in accordance with directions and follow precautions like wearing gloves etc., Pest Oil when used in accordance with directions is also an effective control of aphid.
Fuller’s Rose Weevil can be controlled with Confidor.
Mites (two spotted mite, formerly red spider) the use of Mavrik should control this pest but in the case of severe infestation the use of predatory mites is helpful. Contact Integrated Pest Management. P.O. Box 436 Richmond NSW 2753.
For further information and help in growing roses successfully an informative video ‘How to Care for Roses’ by Ben Swane is available.
If you hunt around second hand book shops ‘Growing Roses’ by Valerie Swane can be found in paperback form at various prices.
SOME SIMPLE GUIDELINES
Always choose a sunny but sheltered site
Prepare the rose bed well prior to planting time
Spread roots out in the base of the planting hole
Water well at planting time
Water thoroughly in summer – roses like summer watering
Check for pests or diseases on a regular basis
Remove spent flowers regularly exactly as you would pick for the vase
Remove any suckers as soon as they appear. The leaves of suckers are different to the leaves of your rose plant.
Check the pH level of soil regularly to maintain optimum conditions for roses.
AVOID THE FOLLOWING
Planting beneath trees – roses do not like competition of tree roots
Avoid planting in saturated or boggy soils or after heavy rainfall
Avoid adding manures or fertilisers in the planting hole – new feeding roots will be damaged if they make contact with these materials at planting time.
Avoid planting too closely for the sake of more plants
Avoid tying climber and standard roses too tightly – figure of 8 loose ties are best
Avoid overhead watering and watering during the hottest part of the day
Avoid fertilsers until the plants are well established (in full foliage).