Last night WeatherBug was blinking a frost alert—the first of the season—and sure enough, there was ice on our birdbath this morning. I hate to admit it, but summer is over. I don’t mind the end of the cucumbers; they were overly prolific this year. And the carrots are safe underground for months to come. What I miss are the fresh herbs that we’re still enjoying. So, they’re moving back in with us.
Fresh herbs are pricy at the market, and they don’t keep very long. Yet, herbs are some of the easiest plants to grow. Since our garden is quite a ways from the kitchen, I have several pots of basil, thyme, sage, oregano, and rosemary right outside the kitchen door. With the weather cooling off, it’s time to bring them inside.
Actually, I heeded the frost warning and hauled the basil indoors last night. It’s very frost-tender, and I don’t want blackened leaves in my pesto. The rosemary, hardy to about 25°F or so, can wait a little while. Oregano, thyme, and sage (left) might survive outside, but I don’t want them to lose their leaves for the winter. So they need a spot indoors too.
(My parsley is growing in the ground, out in my veggie garden. I’ll harvest the leaves and freeze them, then mulch the roots so they resprout in the spring. As biennials, they’ll bloom next year, attracting beneficial insects. Plus, I’ll let them scatter their seeds for future generations.)
When bringing in plants, there are several points to keep in mind. First, make sure that there aren’t any hitchhikers. One or two aphids or whiteflies won’t hurt the plants outdoors—they’re kept in check by ladybugs, lacewing larvae, and other natural controls. But bring them inside and you can trigger an epidemic.
For smaller, sturdy plants such as potted geraniums, a bucket of soapy water will do the trick. Turn the plant upside down and swish the leaves and stems in the bucket, taking care not to lose any soil (I just wrap a towel around the stem).
Since my herbs are in 15-inch pots, there’s no way I’m going to pick them up, turn them over, and swish. So, I spray them with non-toxic insecticidal soap, then go over them leaf by leaf. I pay particular attention to the underside of the leaves and in the stem axils, where pests tend to hide.
Then I check the drain hole. While I’m lucky not to have many slugs, that’s one of their favorite hiding places. Spiders also hang out there. They won’t hurt the plant, but let’s just say I’m not too keen on spiders (to put it mildly), especially in the house.
When I’ve satisfied myself that the plants are pest-free, I bring them in, but I isolate them from my other houseplants for a quarantine period—perhaps two weeks or so—until I’m sure they aren’t going to cause problems. I’m a bit paranoid, but I have a lot of houseplants!
Most gardeners are familiar with the process of “hardening off.” That’s how we slowly introduce indoor plants to the more extreme conditions outside. When bringing outdoor plants in, ideally the whole process is done in reverse. I start by bringing in the plants at night, putting them in the coolest part of the house. Over a week or two, I allow them to adapt to the dryer air and lower light they’ll live with all winter.
Of course, when an unexpected frost threatens, or the weather suddenly turns from balmy to blizzard (as it does in Colorado), there’s no time for such niceties. In that case, I just haul in the plants and hope for the best.
Finding room inside can be a challenge. I locate the pots away from drafts, either from forced-air heat vents or a door to the outside. (I cringe whenever visitors stand at the open door, drawing out their good-byes while precious heat escapes into the cold outside and freezing air shocks my plants.)
I try to give the sun-lovers bright light near a south-facing window. On the other hand, I don’t want the plants too close to the glass. Bright sunlight coming through glass can burn tender leaves, and an extra cold night will freeze them. For small pots, artificial light can help. Ordinary fluorescent bulbs (at least 40 watts or the equivalent) provide adequate light, as long as they’re very close to the foliage and are left on about fourteen hours a day.
My indoor herbs may not make it through the entire winter. I’ve especially had problems with spider mites on the rosemary, and I vow to give it extra attention and regular misting this year. But even a few extra months of fresh eating make the effort worthwhile. Dried herbs simply can’t compare with just-picked!