STILLWATER, Okla. – Gardeners know how handy it is to have all important gardening tools close at hand. For gardeners with greenhouses, it makes sense to keep all essential supplies like tools, extra pots, potting soil and seeds under potting benches and tables.
But a greenhouse should not be used as a storage shed, said David Hillock, Oklahoma State University Extension consumer horticulturist.
“Obviously, it’s handy to have everything you need within reach, but a greenhouse isn’t ideal for storage,” he said. “Greenhouses are humid, which isn’t the best atmosphere for storing some gardening-related items.”
Don’t store metal or wood-handled tools in the greenhouse. The metal will rust, and the high humidity can split the wooden handles. Stainless steel or plastic- handled tools are fine to keep close by for potting up plants, but other tools should be stored elsewhere.
Casey Hentges, OSU Extension associate specialist and host of the “Oklahoma Gardening” television show, said gardening enthusiasts should immediately remove diseased plants from the greenhouse.
“It might seem like a greenhouse is a good place for plants to recuperate, but the moist atmosphere is the perfect environment to spread diseases and pests to your other plants,” she said. “Also, inspect all plants coming into the greenhouse for signs of disease or pest stress.”
While gardeners sometimes need to apply pesticides, the greenhouse isn’t the location to store them. Pesticides should be stored in an environment between 40 and 90 degrees Fahrenheit. Anyone who has experienced an Oklahoma summer or winter knows the temperature often exceeds those limits. Pesticides can catch fire or break down, making them ineffective if they get too hot. A cool, dark, dry, well-ventilated location is the best for pesticide storage. Seedlings are often sold in cardboard plant trays or boxes, and packaged seeds are sold in paper containers. Humidity is not a friend to cardboard or paper, as moisture can ruin seeds. Or, a watering can could accidentally tip over and spill onto seeds. Instead of the greenhouse, store seeds at a cool temperature away from moisture.
Hentges said rodents can be another issue in the greenhouse.
“Mice and other rodents may be able to enter the greenhouse, and they’ll eat your seeds. Not only that, but they’ll also chew on cardboard and other paper and make a mess,” she said. “Also, the high humidity will cause the paper and cardboard to mold, which is a mess gardeners don’t want to deal with. Instead, use any flat pieces of cardboard in the garden to help smother out weeds. Cardboard can also be composted.”
The convenience of keeping these things in the greenhouse may be appealing, but in the long run, it’s not worth it.
It won’t be long until the summer heat turns up the temperature in the greenhouse. As gardeners move their remaining plants outside, also remove anything with an electrical component that shouldn’t be exposed to extreme heat.
“Maintain your greenhouse for its intended purpose of growing and nurturing healthy plants,” Hillock said.
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