Rain, rain, go away…..so the nursery rhyme goes. As goes our thoughts this rainy, wet spring. While rain is important for all kinds of things from our gardens and farms to ecosystems to hydro-electric power to drinking water, there is such a thing as too much of a good thing. Last year we were praying for rain for crops as the drought pressed on and temperatures soared into the 90’s in July and August. This year we are praying the rain stops, at least for a while. We began the month of June at a deficit of 2+ inches of rain, and now, just a few weeks later we are at a surplus of over 3 inches.
Constant rain provides optimal conditions for fungal growth on plants and crops this time of year and into the summer. In a previous article last year, we talked about solanaceous diseases (tomatoes, potatoes, eggplant) such as blight and Septoria, vine crop (cucumbers, squash, pumpkins, etc.) diseases such as downy and powdery mildew, and cole crop (cauliflower, broccoli, brussel sprouts, kale) diseases such as Alternaria and downy mildew. For more info on these diseases, please visit our farm’s blog, http://gardenspotlight.blogspot.com/2011/08/solanaceous-diseseases.html.
Excessive rain also keeps farmers from getting into their fields to weed, plant new crops and mow hay. It also affects the number of degree days. Degree days are a measurement of the heating and cooling of the earth. They are used to determine when to plant crops. Sunshine is necessary for proper plant growth and health. Plants rely on the sun’s energy to convert carbon dioxide (carbon and oxygen) and water (hydrogen and oxygen) into food. This process is known as photosynthesis. A lack of sun delays plant growth and flowering.
Excessive rain soaks the soil and when the soil stays wet for too long of a period, plant roots starve for oxygen and eventually rot. In the local corn fields, where there are low spots, you can see corn plants that have yellowed due to the excessive rain remaining in the soil for too long a period.
Too much rain also depletes the soil of nutrients and if you notice a lack of flavor in your favorite in-season fruits and veggies, it’s probably due to the excessive rainfall we’ve had as the plants are lacking the essential nutrients for proper growth and development. Please see our page on soil fertility for a more in-depth look at how nutrients and sunshine all work together here: http://gardenspotlight.blogspot.com/2011/04/soil-fertility.html .
So the weather affects things in so many ways. It seems in farming lately we are dealing with extremes as far as weather is concerned. Some farmers would rather have more rain than a lack of; others would rather have less rain in order to be able to irrigate and have more control over the application of nutrients added to their crops. It looks like finally this week, we will have more sunshine than rain. I hope it stays that way. Here’s to a successful farming and gardening season to you all! See you at the farmers’ markets.