Can’t see the Trees for the Lawns?

Each spring and early summer it is amazing how fast grass, weeds and lawns can grow. The combination of longer, warmer days and the occasional shower makes for ideal growing conditions, and there is always something to do in the garden.

For most of us, there will be the need to mow our lawns (if we have them) fortnightly, if not weekly, and if things have been a bit out of hand, we may even need to use a trimmer to cut back the weeds. You might begin to wonder if there is anything we can do to improve the situation?

Australians as a whole seem to be a group of lawn shavers rather than of lawn mowers. Many of us cut our lawns far too short! Grasses are living things and grass leaves grow from the base, which is just above the soil surface. So we should be cutting lawns higher, and although the height of the cut varies with the species of grass, soil type and weather conditions, in most instances we should not cut closer than 50mm.

Cutting lawns too short has a number of consequences, which are often unknown to home gardeners:

• Very short lawns use more water than longer lawns. With the water rating systems moving to charge more for water and based on water usage this could see substantial savings on water bills for those who leave lawns to grow longer! And, of course, the extra water used depletes water storages
• Cutting too short often damages the grass, and can result in dead patches developing in a once lovely lawn
• Dead patches in the lawn allow weeds to invade, which leads to unsightly lawns and the need for tiresome weeding.

So try to remember not to cut your lawns too short.

While on the subject of lawns, I would remind everyone of the need to protect trees growing in lawns from trunk problems due to motor mower damage, as people try to cut too close to the trunk. Trees are major assets in any garden so don’t cut lawns around tree trunks!

Over the past few years the most common problem I have seen with trees is trunk damage from mowers and weed trimmers. Never cut closer than about 150mm, and remember that young, thin-barked trees are particularly vulnerable to weed trimmer injury.

The best way of dealing with grass or weeds growing around the trunks of trees is to hand remove material, use a suitable mixed particle size mulch.at a depth of 75mm or use an appropriate herbicide at the right concentration. In many instances organic mulches that you can produce yourself will prove ideal.

When you work in your garden remember that it is the trees that make a major contribution to its ambience and beauty and which shelter your garden and house from weather extremes. So make sure you don’t harm them when you are mowing your lawns and weeding. See trees as the assets they are and do all you can to protect them!

Your garden not only gives you pleasure, but adds real value to your home and the quality of your life. It is worth doing things properly in the garden as you will be amply rewarded for the time and money invested!

References

Harris, R.W., N. Matheny and J.R. Clark. 2004. Arboriculture. Integrated Management of Tree Shrubs and Vines in the Landscape, 4th Ed. Prentice Hall, New Jersey.

Articles in Gardening Australia Magazine

Article and photographs copyright to Greg M. Moore, Senior Research Associate, Burnley College, University of Melbourne