Spring showers good news for plants
April's here, and, weatherwise, anything can happen. Northerners know better than to put away their snow shovels, and even a Mid-Atlantic gardener might think twice about putting all the tomato plants in the ground, springlike though it may be. Snow or frost may still appear.
Gardeners tend to be philosophical about weather events, partly because they're beyond our control and partly because there's usually an upside to them.
Snow is a case in point. To a cold-climate gardener, a consistent snow cover that lasts all winter is nature's mulch. It protects any perennial plant hardy enough to take the cold, without the heaving and breakage of plant roots that comes with alternating freezes and thaws. On the other hand, freezing and thawing is great for the soil's structure, opening up crevices that absorb water, nutrients and air.
Snow is also referred to by old-timers as the poor man's fertilizer. That's because snow and rain absorb nitrogen from the atmosphere and carry it to earth, adding as much as 10 pounds per acre in a form (nitrates) that plants can use.
Snow does it better than rain, because it seeps slowly into the soil rather than washing away as runoff.
Unfortunately, air pollution now adds way more acidic nitrates to precipitation than before, leading to algae blooms, damage to animals and plants, and other woes. So while a storm might make the air seem fresh and cleansed, it may have brought some trouble with it at ground level.
An excess of water, whether from heavy rain or rapid snowmelt, can be good or bad depending on how your ecosystem is managed. Flooding can lead to the loss of precious soil if a gardener leaves it exposed, without the protection of nature's catchment system of plant roots. In ancient Egypt, the annual flooding of the River Nile was so beneficial to the fertile lands on either side that the river was believed to embody the god Osiris. It's all about giving water a right place to go.
Wind is another great force in which nature giveth and taketh away. It's annoying when it drifts snow onto the driveway, knocks over the corn or rips the row covers off the broccoli. But a windy night lessens the chance of frost. A windy day makes it harder for mosquitoes to fly.
If you live by the ocean, sea breezes not only cool and refresh, but they also carry a bit of the ocean with them. Seawater, in the form of windblown spray, delivers a healthy dose of trace elements that make garden plants thrive. No wonder seaweed fertilizers are so effective.