The short answer is: yes.
While mature trees have enough root spread and depth of growth to survive droughts and dry seasons, they could sometimes still use your assistance. If it has not rained for a month or more, even your oldest trees could be depending on you for supplemental moisture.
A few things to keep in mind when watering mature trees, as opposed to younger trees:
- Younger trees have their roots closer to the trunk, sometimes even still enclosed in the root ball. While a younger tree wants water near the trunk, a more mature tree wants more water around the perimeter of its canopy. The edge of the canopy is called the “dripline,” and you want to water even beyond that dripline. The roots will extend out even further than the canopy on a mature tree. Watering too close to the trunk doesn’t hydrate your tree as much as you’d like, and leaves your tree vulnerable to mold or fungal growth on the trunk.
- You do not want the trunk to rot. If you can put mulch around the trunk, three or four inches deep in an even layer, but not right up against the trunk, that is healthier than having grass growing right up to the edge of the trunk. Grass growing right around the trunk can intercept the water. Keeping that turf-free circle around the trunk will help it survive and thrive. Done properly, mulching helps your tree stay hydrated with slow-release moisture; done improperly, mulching can do more harm than good.
- You do not want to fertilize drought-stricken trees. Adding fertilizer to a stressed tree will encourage a rush of new growth, and it is new growth that the tree is too thirsty and weak to maintain. The tree would then need more water than it can currently find to support its new growth. Also, the salts in fertilizer will exacerbate the difficulties the mature tree is already having in the dry weather.
Keeping Mature Trees Healthy
What you want to do is to provide enough supplemental water to keep your mature tree healthy through the drought. However, you do not want to over-water. If you over-water, the tree will sprout new canopy growth as it would in a rainy season. Unfortunately, the dry soil cannot support this additional canopy growth, so this mature tree would now be dependent upon your irrigation to support its new growth, rather than just relying on its natural surroundings as we would prefer.
Most of a mature tree’s roots are relatively close to the surface — between a foot and 18” below the top of the soil. The more the roots extend deeply into the soil, the more stable the tree will be and the easier time it will have finding proper subsurface hydration during dry periods. We want to encourage those roots to extend deeper into the soil. Therefore, it is better to provide your tree with a deep soak once a week than several lighter-watering periods throughout the week. When the water you provide has had the chance to soak down several feet into the soil, the tree’s roots are encouraged to grow deeper down, which is healthier for the tree in the long run.
Best Way to Water Your Trees
A smart strategy for tree watering is to use a soaker hose. These hoses are designed to be laid out in a spiral around the tree trunk, extending out to the edge of the canopy and beyond. These soaker hoses slowly disperse water over the course of an hour or two. This slow release of the water is better for the tree, and it is also much more efficient in terms of the amount of water you will use.
To test the soil moisture levels around your mature tree, poke into the soil with a long (over eight inches) screwdriver. If the screwdriver goes easily into the soil, your soil is moist enough for your tree. If it is more difficult to push the screwdriver in, then chances are good that your soil is too dry. If you cannot push the screwdriver all the way in, then it is safe to say you should be watering more.
Need Tree Advice in Cincinnati?
We can’t all be experts at everything. Luckily, you know a Cincinnati Tree Expert – the team here at Tree Images! Contact us today for assistance with caring for the health of your trees, whether in dry times or wet. Wherever you’re located, your local tree service company will have the best local advice on how to care for your trees according to your local climate.
