By Sharah Truett
Howdy farmers! If you struggled to keep fruit trees healthy during last year’s drought, you are not alone! My ancient and beloved Italian Prune Plum almost gave up the ghost due to parched soil. I never had to water it before, but times are changing. This year, I searched the WSU Publications for advice on how to keep fruit trees going during drought. Here is what I learned.
The time of most rapid cell growth in a fruit tree is from flowering to four weeks after blooming. This period will determine the size and quality of the final fruit. It is also the time of fruit set. If the tree is too dry you won’t get the quantity you are looking for. If it is a dry spring, you may have to supplement soil moisture with irrigation.
The time of final fruit swell is very important as well. Soil dryness during this time can reduce the fruit size and quality. For cherries, plums and pears the important time is the last 3 weeks before you harvest. For apples it is the last two months before harvest. If you don’t have quite enough water to last the entire dry season, you can reduce watering during fall dormancy. This won’t affect the tree as much as reducing water at other times.
Here are a few steps you can take during a drought to make your water go further.
- Use a soil moisture monitor to figure out best times to water and best times to hold back on watering.
- Mow the cover crop at the base of the trees closely to conserve water. Make sure to keep the area around trees clear of weeds and grass.
- You can thin your fruit heavily to reduce water consumption. This will increase the quality and size of the remaining fruit and keep your tree healthier for the next year.
- Use an irrigation scheduler to make sure you are applying the correct amount of water and not overirrigating
- If the drought is very severe, you could consider heavy pruning or “dehorning” of the tree to reduce water use. This will greatly reduce production this year but will keep the tree alive for the next year.
Check out the WSU Extension Publication called “Drought Advisory Tree Fruits” for more detailed information about these strategies.