I know I sound like an alarmist. It’s been warm all fall, and now that we’ve had just a tiny appetizer of cool weather, I’m talking about carting plants in for the winter.
We’re still a month away from the average date of the first killing freeze here in North Texas, so you’re saying to yourself, “Slow it down, Neil. Back off from the panic button.”
And that’s fine. I’ve been accused of a lot worse, but I’ll also remind you of those late October first freezes we in Metroplex suburbs have faced in very recent years. It does happen, and wise gardeners get themselves ready.
Which is to say that it’s time to start thinking about which plants you’ll want to save over the winter and which will head to the compost. It’s a tough decision, but it’s one we all must make. Let me try to simplify things for you by sharing my own thought processes.
My first criterion goes to those plants that would be difficult to replace. I have several unusual foliage plants that I’ve been nurturing for 25 years or longer. They get top priority. Two are unusual types of peperomias, one given to me by the late Ralph Pinkus, founder of North Haven Gardens in Dallas. Others are great rhizomatous bromeliads I’m growing in pots so that I can sink them down into beds. I’ve found that armadillos leave them alone.
As you may have seen me write or heard me say, for all of my adult life I’ve been growing selections of coleus that are propagated from cuttings because they don’t form flowers and go to seed. (Seeds stop the growth of new leaves with coleus.) I guess if I made a list of these “favorite” plants that I feel I must save, there would be 40 or 50 of them.
I also put plants that would be expensive to buy again in the spring on that list. If I have room for them, I’ll save them as well. They may not be rare or irreplaceable, but why pay twice if I can save them.
But the plants that I save must be types that will survive the winter in top condition. I don’t save copper plants, for example, because no matter how I try to protect them, they seem to look miserable come spring. And caladium tubers are just too hard to store. Sure, they’re a bit pricey to buy every year, but the quality and performance are so much better when I get fresh starts in the spring.
Conversely, I usually save a couple of nice wax begonias just to have spots of blooming color in mid-winter. I’ll pinch them back by half or more to encourage new growth. And I might do the same with a potted geranium if I still had a nice one left when first frost occurred. But it would be a complete waste of time to try to save pots filled with pentas, angelonias, moss rose or periwinkles. Start over with them.
Curiously, some plants are hurt at temperatures far above freezing. It’s called “chill damage,” and several tropicals like aglaonemas, dieffenbachias and bougainvilleas suffer from it when exposed to temperatures of 45F-48F. They begin to wilt and their growth stalls, often beyond recovery.
It’s best if you begin to “harden” your plants to get them ready for winter. Gradually acclimate them to less fertilizer and slightly less water. You don’t want to let them get dry, but you also don’t want to do anything to encourage soft, succulent new growth at a time when they need to be shutting down.
If you have tropical plants that have been in unusually bright lighting over the summer, stairstep them down to darker conditions before you bring them indoors. Your goal once you get them inside will be to maintain them status quo, not to encourage them to grow until spring. Just to have addressed it, artificial lighting indoors won’t be sufficient to make up the difference.
Perhaps you figured out several paragraphs ago that I have a greenhouse. That’s where most of my plants go. What I’ve written, however, applies to plants in your home. But if you’ve been considering buying or building a greenhouse, let me encourage you. They’re fabulous.
I’ll write more about greenhouses another time here, but know that bigger is better when it comes to greenhouses. Larger houses give you more room so you can accommodate more plants. But it also provides a greater volume of air, and that slows the rate of temperature change. Small greenhouses overheat quickly on clear days in mid-winter.
This is about the point in any discussion when someone asks about keeping plants in the garage over the winter. That’s when I boldly warn that the garage may be the worst place ever for overwintering plants. Unless your garage has full-length glass windows and an abundance of skylights, it’s going to be cold and dark in the garage in mid-winter. Your plants won’t be happy, and few will survive. They’ll face mammoth recovery issues come springtime. Use the garage only for short-term protection of patio pots of outdoor color like pansies during extreme cold in the winter.