Tips for pruning without spreading disease

Soon thousands of gardeners will be getting out their secateurs and pruning saws and begin the annual pruning of roses and deciduous fruiting trees and plants.

Why do we prune? There are several reasons for pruning, keeping a good shape, removal of dead or spindly wood, preventing woody-ness, shaping so that all of the plant obtains as much sun light as possible, encouraging flowering and fruiting, preventing dense growth, encouraging new growth and removing diseased wood.

On roses we tend to prune to obtain the best from the plant. A Hybrid Tea for instance will likely be pruned hard, leaving a few strong canes to produce a smaller number of perfect blooms. On the other hand a Floribunda, from which you want a mass display of blooms, will have many more canes and will not be cut back as hard as a Hybrid Tea.

When we prune we are opening up the plant to diseases that may enter the plant through the cuts causing problems, or even resulting in the death of the plant.

In winter the worst disease is silver leaf, which attacks stone and pip fruit, roses, poplar, willows and escallonia hedges. The disease turns leaves silver and the leaves become smaller. Infected branches die back and are killed when the fungal mycelium stops the sap flow. Fruiting bodies form on branches soon after they die. These are about 15-30mm across, sometimes larger, and may look like small brackets.

They are likely to appear when the weather is cool and wet. It is during cool wet weather that the fruiting bodies release their spore which can then enter the pruning cuts of host plants. During dry weather the spores are not released and this is the reason that summer pruning is done in preference to winter pruning on many fruit trees. This does not help with roses as the main pruning is a winter chore.

There are other diseases such as die-back that can also enter fresh wounds.

In the past gardeners would seal cuts with the aid of pruning sticks or pastes to reduce the instance of disease. But over time many of these products have escalated in price making them an expensive item, especially if you only have a few roses. So many gardeners have stopped using this protection as the cost of some pruning solutions can mean you could buy one or two new roses.

Some have used alternative, cheaper protection such as mixing a copper into either petroleum jelly or acrylic paint and applying this to the wounds.

Some will just spray the plants after pruning with copper to give a degree of protection.

You can make up a spray protection for pruned cuts by adding 7ml of Liquid Copper to a litre of water with 1ml of Raingard added and spraying this over all cuts.

Very convenient to use, just squirt a little of the solution on all wounds as you prune. Another great advantage is that you can spray the solution onto the cutting areas of pruning tools between plants. This will aid in the prevention of transfers of fungal and bacterial diseases between plants. Dead wood can easily have fungus diseases working on the wood to break it down.

Sometimes one may have a disease such as silver leaf in a rose or tree and not beware of it and transfer the disease to other plants while pruning. Silver leaf can be deadly if not treated in the early stages with Perkfection.

The solution not only covers the freshly cut wound but enters into the wood in the area of the cut giving both internal and external protection.

The solution will keep well out of sunlight with the top firmly secured.

Gardeners can now protect their roses and plants with an affordable home made solution.

Rose planting tips
Roses can be lost when their roots are not kept moist during and after transplanting.

If you buy roses that are not bagged up or in containers, then you should submerge their roots into a bucket of water as soon as you get them home.

Leave them in the bucket for a day and then plant. If you cannot plant them at that time, then heel them into a patch of garden where the soil is moist to wet.

If the roses are in a bag or container ensure that the mix is kept nice and moist till you lift them out of the container and plant them. It is fatal if the roots of roses dry out for any length of time.

Then you dig a hole to plant a rose, before planting, fill the hole with water and leave till most of this water drains away (if the water table is high and there is already water at the bottom of the hole then don't add more).

Sub soil may be dry even if the top soil is moist and we need to ensure that the soil in the area of the roots is nice and wet. Likewise for the first year of the rose's life, in its new location, the rose must have adequate moisture in the root zone. You may like to cut the bottom off a plastic cordial bottle and plant it so the neck of the bottle is in the root zone. This allows you to water the roots when the top soil is very dry.

Otherwise a new rose will need about a bucket of water a day during drought times or when the soil moisture level becomes low.

New roses have not been pruned, they have been cut back to make transporting easier.

Normally about 4-6 weeks after planting a new rose you would do the final pruning.

The first problem the roses will face in the new season is attacks of aphids on the new shoots and buds. At the first sign spray with Neem Oil and Key Pyrethrum and repeat when new aphids come along. It's easy to tell with these natural sprays, as the aphids are dead within 24 hours from spraying.

A few gardeners have told me that applying Neem Tree Granules to the soil under the roses had helped with aphid control without the need to spray as much.

You may like to try this yourself this season and I would be interested to hear the

The Southland Times