Originally Published: August 18, 2017 5:58 a.m.
A season of rain is as trying as a season of drought. Excess rain creates gooey soil, which is no fun for planting if you are a human and no fun for growing if you are a plant.
Roots need air, and day after day of rain can fill all the soil pores with water. The result: Roots have trouble absorbing nutrients and even water.
HELP FOR CLAY SOILS
Incessant summer rains rarely present a problem in soils that are well-cared for or sandy. In clay soils, waterlogging can be avoided if they are treated right. Adding heaps of organic materials such as compost, leaves and straw to clay soils causes the small clay particles to aggregate into larger units. Not walking on or working a clay soil also allows aggregation over time. Larger aggregates have larger spaces between them, so well-aggregated clay soils drain water well, just as water drains well from the large pores within sandy soils.
If conditions are really watery, construct raised beds for vegetables and flowers, and large mounds on which to plant trees and shrubs. Of course, soil used to build up the raised beds or mounds should drain well.
If soil conditions are worse still, move your plants somewhere drier.
PROBLEMS EVEN IN WELL-DRAINED SOILS
Alas, even with perfect drainage, a wet summer can bring on problems unrelated to the soil. Plants might “lodge,” for example: Growth is so lush that stems flop over because they can no longer support themselves. Corn plants standing neatly like soldiers one day might suddenly, even with calm air, bow low as if hit by gale-force winds.
Speaking of lush growth, abundant summer rains will also have weeds thriving.
And plants will experience less sunlight during a wet summer. Less sun means less fuel to make delicious tomatoes, peppers, apples and other fruits.
You could also blame rainy weather for poor fruiting of peppers and delayed fruiting of tomatoes. The effect of rain in these cases is indirect, the result of poor pollination.
Excessive rains also can bring on pests. Most fungi thrive in moisture. A dramatic demonstration of this would be the near-leafless crabapple trees frequently seen in wet summers; moisture-loving scab and rust fungi are mostly responsible for these trees’ fall from their spring glory.
Adequate spacing and pruning promote good air circulation so plants dry more quickly, lessening disease problems. Still, the threat is increased during a rainy year.
Crawling pests may or may not enjoy abundant moisture. Needless to say, wet conditions are heavenly for slugs and mosquitos.
TOO WET OR TOO DRY?
I prefer a dry summer to a wet one. The effects of drought can be mitigated by mulching and irrigating, but there’s little you can do when days of rain cause poor fruiting and an increase in diseases, slugs and mosquitos.
Summer weather in many regions is variable, wet one year and dry the next, but there’s something to appreciate either way.