Armidale gardening: Care for your precious trees

Birch trees: Birches are a species of tree that can wilt quite readily in the heat of a summer day.
Birch trees: Birches are a species of tree that can wilt quite readily in the heat of a summer day.

It is a sobering thought that it will take 20 years to replace a 20-year-old tree if it dies. It is worth properly watering your trees, especially those five or less years old.

Closely observe your trees for signs of water and/or heat stress. Trees such as birch (Betula spp), dogwoods (Cornus spp), sycamore (Platanus orientalis) and prunus can wilt quite readily.

Watering can remedy drooping leaves overnight, while trees with wilting leaves browned at the edges need additional water.

Other early signs that a tree is under moisture stress include unusually early autumn colours and for conifers, the needle tips may go yellow or brown. Often, if a large part of a conifer has browned off, it can be on its way out, so check closely for those early signs.

To tell when to water without waiting for signs of stress, a moisture meter can be useful, or find a smooth rod about half to 1cm in diameter and push it into the soil. If your rod won’t go into the ground more than 7-10cm, it’s time to water. After you have watered your tree, you should easily be able to push the rod into the ground at least 30cm or more.

There is also a general guide that a tree needs 45 litres of water for every 2.5cm of the diameter of the trunk. Therefore a tree with a 10cm diameter trunk will need 200 litres or a 44 gallon drum of water to fully water it when the soil is really dry. Make sure you water the root zone, which is roughly under the outer leaves of the canopy.

Jobs for February

Keep basil and other herbs nipped back to prevent flowering. Growing mint in troughs covered with a wooden frame with fine mesh not only excludes pests that can ruin the foliage, but also prevents runners invading adjoining garden beds.

Pick up and destroy all fallen and diseased fruit to prevent re-infestation of fruit fly and coddling moth.

The Armidale Garden Club has its first meeting for 2017 on Thursday, February 23. Meetings are held at the Uniting Church Youth Club Hall, off Rusden St, at 7.30pm on the fourth Thursday of each month. If you would like more info, call 0412 589 414, or just come along!