At the moment, for me, the well has run a bit dry; figuratively that is. This post is a bit behind schedule due to a minor case of writer’s block. My apologies. Today I finally realized that could serve as inspiration; inscription to write about how figurative famine or flood might influence the fruit crop.
Late July is a time when, for many fruit gardeners, the effects of water in the garden become magnified.. For some, this year there has been a deluge for others, drought. So, let’s dive in; relatively speaking and look at what you can do about it.
Too Much Water
For those areas of the country that have been exceedingly rainy, here are some problems you might be encountering and some suggestions for how to overcome them:
• Fungus diseases. Fungus spores are spread and develop in the presence of water. So lots of water, be it from rain or a sprinkler, coupled with warm summer temperatures will encourage growth of many diseases. Add ripening fruit with softer skins and higher sugar content and you face formidable problems. The best approach is proactive. Keep fungus diseases in check from the very beginning of the season. This is especially important for some of the major diseases such as apple scab, brown rot, and mildew. Good disease prevention early in the season equals fewer spores and secondary disease development at this time of year. If you have already missed the boat and diseases are sailing full-steam thru your fruit garden, concentrated on sanitation—remove left over fruit that harbors spores to avoid a serious repeat problem next year.
• Waterlogged soil. Roots need to breathe. They need some pore space in the soil for proper metabolism. There is no quick fix for this. Regular additions of organic matter and compost will improve soil texture over time (sometimes lots of time.) If you are selecting and preparing a site for new plantings, keep drainage in mind to minimize or avoid this problem in a rainy year. Check here for more information on soil texture and drainage. Waterlogged soils often causes the next symptom:
• Yellowed leaves & defoliation. These are two outwardly visible symptoms indicating your fruit trees or berry bushes may be encountering a moisture problem. The problem could be either excess, more likely if the leaves are yellowed; or insufficient water. If the problem is excess, the solution was already mentioned above. We’ll address lack of water later on.
• Nutrient leaching. Nitrogen especially, is quite water-soluble. Excessive rainfall or over-watering may carry it through the soil and out of the plant root’s range. If you are experiencing lots of heavy rain, it may be worthwhile to feed smaller doses of nitrogen more often; for example 1/3 of the annual dose broken into 3 applications—one in early spring, another during fruit swell and the last a month later as the crop is maturing. Avoid fertilizing beyond mid to late summer or plants may grow too succulently and be susceptible to cold injury at the start of the winter.
Not Enough Water
Although solutions to dry conditions may involve temporarily more work on you part, drought may be easier to deal with (at least you can try to provide moisture) than a non-stop deluge that is hard to deter. Let’s look at the flip side of the “flood” problem and what you may be able to do about it. Some problems that may crop up include:
• Wilting. This is the first and most common sign of a plant in water stress. The obvious solution is to provide water to supplement what nature has failed to provide. Trickle irrigation is an effective and water conserving way to do this. One thing to remember with trickle, is that it needs to be started early in the season, before the ground has truly dried out. It is not easy to replenish the soil reserves with the small quantity of water provided by a trickle system. The benefit of trickle irrigation is that it provides moisture directly in the root zone, where it is most needed without wasting excess water.
• Scorched leaves and defoliation. These two symptoms are serious indicators that your plant is suffering more severely. Again, you will have to step up and fill the water gap. Especially if you did not start trickle irrigating earlier you may need to provide a deep soaking, either by hose or bucket, to fully wet the root zone and bring the plant out of stress. If you are under water restrictions consider collecting gray water (from cooking, hand-washing, and other tasks where water may be “dirty” but not unusable.) As long as there are no pesticides or high levels of salts or fertilizers in the water, it should still be usable for plants. Once at least moderately rejuvenated, you can continue to maintain your fruit trees, berry bushes, or vines with trickle irrigation.
• Death of young transplants. Newly planted fruit trees and bushes are more sensitive to lack of water since their root systems are not yet fully developed. Close monitoring and extra TLC, in the form of timely watering, are critical under drought conditions. You can learn more about how much water you need to provide here. [LINK]
• Small fruit size. Fruit size often suffers when the plant experiences a serious water deficit. You can help the plant by thinning the fruit a bit more aggressively. With a reduced number of fruit the tree or bush has to support, it can channel its energy into properly developing the remaining crop. Hard as it is psychologically to remove fruit from the plant, it is a wise short-term sacrifice for long-term gain.
• Premature fruit drop. This symptom of moisture stress is one step beyond, reduced fruit size. In self-preservation, the fruit tree or bush will drop fruit that it can no longer support. You will do your water-stressed fruit garden and yourself a huge favor if you thin fruit early as suggested above.
• More severe damage by pests. Drought-stressed fruit trees, berry bushes, and vines are weakened plants. This leaves them more vulnerable to pests. Mites tend to multiply rapidly in hot temperatures that often accompany drought. Mites sucking sap from already dried leaves exacerbates plant stress. Borers often find it easier to invade weakened tissue and often do more than the normal amount of damage in times of drought. Be especially vigilant for signs of these as well as other pests and implement control steps quickly in order to maintain plant strength.
• Root rot and other diseases. Weakened root tissue often sets up the opportunity for soil-borne root rot organisms to enter. Armillaria root rot as well as Nectria and Cytospora canker on stone fruit are particularly opportunistic. Symptoms are not likely to occur immediately. Rather the damage will make a delayed appearance a year or two later. Be prepared and try to proactively provide optimum care to your fruit garden to keep it strong next season and in the years to come.
Moisture-related Problems in Specific Fruit
I’ve covered general recommendation for managing water needs in the fruit garden during unusual rainfall or lack thereof. Let’s look now at a few specific fruits and their unique situations.
Strawberries. Normally strawberries are given fertilizer following renovation rather than early in the spring. When renovating during drought conditions, you may want to reduce the amount of fertilizer or split the applications, saving some of the application for when natural rainfall or adequate water supply becomes available. Reducing fertilizer may reduce growth of new plants, which is not ideal, but it will also reduce the amount of leaf area for moisture loss through transpiration. It is a trade-off that you will have to judge based on your individual situation.
Sweet cherries. Fruit cracking often occurs when there is rainfall shortly prior to harvest. Little is understood about the reasons why this happens and researchers are still searching for what can be done to prevent it. At the moment any proposed solutions are far to complex and expensive for home garden application. The only marginally effective solution for the home gardener may be to choose less susceptible varieties, but even this is not a guarantee. Van, Sweetheart, Lapins, Rainier and Sam could be varieties to consider. Bing cherries have a high incidence of cracking and may be best avoided in areas where fruit cracking is a frequent problem.
Peaches and nectarines. Split pits in peaches is not fully understood and can happen even in seemingly “normal” growing seasons. Two factors that may make it more prevalent in seasons of drought are one, the recommendation to thin fruit heavily and two, the sudden excess of water the fruit may receive from rainfall if drought ends or if watered heavily at the time of pit hardening and fruit swell. Both these factors appear to make split pits more common in susceptible varieties.
General Practices for Effective Water Management in the Fruit Garden
To close, remember that the following practices will help effectively provide conserve, and maintain adequate moisture for your fruit garden under normal rainfall:
• Apply mulch around the base of fruit trees, berry bushes and fruiting vines.
• Trickle irrigation should be started before soil moisture reaches a deficit level.
• Water during the coolest part of the day.
• Diligent control of weeds reduces competition for moisture.
• Providing an appropriate amount of water regularly is important for strong plant and fruit growth.
• Time watering to coincide with critical growth periods—root development, fruit swell, flower bud initiation—if your water supply is limited.
So folks, when it rains, sometimes it pours. Let’s hope that all our gardens receive the appropriate amount of rainfall for the remainder of the growing season and that my ink well (or keyboard, as the case may be) is also duly replenished.