Grow Guide: The Best Pots for Cold Weather and Ants in the Compost
Gardening expert and certified wit Felder Rushing answers your questions and lays down some green-wisdom. You can get more of your Felder fix at www.slowgardening.net.
Do you settle arguments? A friend says plastic pots are better for outdoor plants in the winter, to protect plants from cold damage, but I think clay works better.
How about we split this one down the middle?
I actually have several dozen potted plants outdoors all year, in both clay and plastic pots, and winter is a real challenge for borderline hardy plants, especially in really cold parts of the country.
Anything that will help keep roots from freezing while not cracking during freezes will do — plastic, sturdy non-porous clay, metal, wood, or even old car tires. So it’s mostly a matter of aesthetics.
However, some inexpensive terra cotta clay pots, while thick enough to protect roots, can absorb water which can freeze, expand, and flake or crack. Plastic, on the other hand, which comes in many decorative styles and colors, may not crack as easily (though it most certainly can), but is not as thick as clay and may not offer the freeze protection plant roots need. Plus, as potting soil dries out, it tends to pull away from the sides of plastic pots, which can let freezing air get down around roots.
I keep my plants well watered in the winter, because a lot of winter damage is from plants drying out in the wind while roots are dry or frozen and unable to absorb moisture. Watering can help thaw roots in nice weather, and, when it freezes, can help protect roots better than would cold air seeping into dry potting soil.
At any rate, while I love how my clay pots look, I also appreciate the lightness and versatility, and longevity, of plastic. Sometimes I double up my pots, putting plastic pots down inside more decorative clay pots. This not only look nicer but acts as a double insulation.
Finally, I group pots together for protection from the elements, and put mulch on top of all exposed potting soil and in between the pots as well.
Help! I have ants in my compost pile! What can I use to get rid of them?
My first inclination is to say “No big deal” because ants got to have a place to live, too. And where better than in a warm, moist, aerated pile of stuff? And actually, in the big picture, they don’t really harm the compost process. Besides, insecticides for ants will harm or kill worms and other beneficial critters in the pile.
But their presence tells me your compost is not very active. If you simply turn or aerate the pile from time to time, the compost materials will break down more quickly, and it will keep ants on the move.
Part of the year I live in the South, where venomous fire ants have been troublesome in my compost bins. There can be several thousand ants in a single colony, with each fast-moving ant having the ability (maybe even the desire) to sting repeatedly when disturbed. And they have been known to use other, more beneficial compost critters for food.
Steam ‘Em Out
Because you really shouldn’t use insecticides in the compost, try a simple thermal trick to get rid of them. Turn your pile, making sure it is well aerated, then wet it down pretty well, and cover it with a sheet of clear plastic. This traps energy from the sun, which can heat up the water and steam the ants out of your way.
This may not get rid of fire ants, which can tolerate a lot of heat and just move down deeper in the pile. But I use it on a smaller scale when “harvesting” compost. I shovel as much as I want to use into a wheelbarrow (working fast, to keep ahead of the ants), then wet it down and cover it with the clear plastic. They leave pretty quickly.
At any rate, see if you and the ants can learn to just get along – unless, of course, they are fire ants!