Nature has been playing the good cop/bad cop game. A couple of weeks of balmy spring weather gets us thinking it is safe to go back into the garden, then - wham! - the jet stream dips and brings us a little bit of Canada. What do Canadians breathe when all their air comes down hereftI know I'm in trouble when the TV weatherman warns to bring tender plants inside. Hah! That's fine for the person with two geraniums on the front porch. It's a bit more problematic for an aging man with achy muscles and dozens of large, heavy pots. Not to mention a wife who likes to walk through the kitchen without a machete.
One of the advantages of killing as many plants as I have in my life is that you learn what they can take and what they can't. Cold is not an on/off or a yes/no kind of thing. Different plants have different reactions to different degrees of cold.
Those geraniums on the front porch, for instance, won't really mind an occasional dip into the 30s. In fact, they'll even survive a frost. They may look a little ratty for a while, but they'll recover quickly.
The pepper seedlings on the picnic table in the back yard are another story. They don't even like nights in the 40s. Maybe it won't kill them, but it will slow them down at a time when you need strong, steady growth.
Sometimes different parts of the same plant can react differently to cold. Thirty degrees can kill flower buds on plants that will otherwise survive.
I have two small lemon trees, and during the recent cold snap, I moved one inside and left one out, but covered. The one I moved in had tender new leaves, which are more easily damaged by cold than mature growth.
I started moving plants outside from the sun porch and the sunroom and the basement when the first hint of warmish weather beguiled me. The go outside in an approximate order, the toughest first, the most tender last. Over three weeks or so just about all of them had moved out. When the night temperatures turned mean, I gave them various degrees of protection in reverse order.
If night temperatures are expected to be within a degree or two of 50, I'm home free. I can go to bed and sleep well.
Mid 40s and I move warm weather seedlings inside - the peppers and tomatoes and impatiens. That is, if I got any impatiens seeds to grow. I keep them all on a large tray, so it's easy. If I forget, they'll survive, but they won't like it.
If it drops into the upper 30s, I start spreading linen. In a couple of weeks, I'll start arranging plants so they look nice. Right now they are arranged by their cold sensitivity. Upper 30s, one group gets covered. Lower 30s, a couple more groups. Below 30 and the patio looks like a Christo installation.
Anyone married more than a few years has old sheets way in the back of the linen closet. Move them to the garden shed and put them to a better use. I've seen plastic used for cover, but it radiates heat. You want it to hold heat.
As summer seems more certain, pots may be placed on porches or steps or tables, but for now they should be on the ground. Soil is a heat sink. A sheet will hold the warmth that radiates from the ground, an edge you don't get when the plant is raised off the ground.
You don't really need to secure the cover at the bottom. Since warm air rises into the canopy of the cover, gaps at the bottom do little harm. If it's windy, you can hold covers in place with clothespins. Remember clothes-pins?
Now the sheets are all folded and back in the garden shed. Though it's hard to fold sheets with your fingers crossed.
o Duane Campbell, a nationally known agricultural expert, can be reached at R6, Box 6092, Towanda, PA 18848 or by e-mail at email@example.com for questions or comments.