The Big Freeze

We are supposed to get a hard frost tonight so for all intents and purposes our growing season is over. Last weekend I brought in my tropical patio plants after a touch of cold got my taro. It is recovering but several of the leaves are toast. At the last minute today I decided to try to over winte my rosemary plant. I like cooking with fresh herbs and it was great having an herb container right outside my kitchen door. The basil had gone to flower months ago, but the thyme and rosemary were doing well. Thyme is a perennial, even here, but not the rosemary. Since it was going to die anyway I figure I don't have anything to lose by bringing it indoors.

There are a few things to remember about bringing plants indoors. More than likely I will have brought in a few unwanted guests (insects) with my plants. I can use systemics on my tropicals but not on edible plants. I can get sticky traps and wipe down the plants to try and physically remove any insect eggs from the leaves.

Usually the plant will undergo a kind of "culture" shock when brought indoors. Even the sunniest spot in your house is not the same as being outside in the sun. You may notice the leaves drooping or even dropping. Resist the urge to water unless you have checked the soil and found it dry. Dropping leaves is a natural part of the plant's effort to acclimate itself to its new environment. Eventually (hopefully) the leaves will grow back and these new leaves will be acclimated to the new conditions. Also, resist the urge to fertilize. Feeding a plant when it is not growing much causes the new growth to be weak and leggy.

I have a spot behind my kitchen sink that is pretty sunny and also conveniently located for cooking so that is where my rosemary will go. I hope it likes it there.

Another factor in surviving winter months for all house plants is humidity. When the furnace is running it really dries out the air and this is bad for most plants. Most plants like about a 50% humidity level. You can increase the humidity around the plant by misting it periodically or by placing trays of water near the plant. Lori always recommends filling a saucer with pebbles and then adding water. Put the plant on top of the pebbles so that it is not actually sitting in the water. This will create a constant humidity dome around the plant.

Over Wintering Tropical Plants

Saturday morning I stepped out on my back deck to discover the temperature had dropped so low overnight that my taro plant (colocasia) leaves were all curled. I drug it in the house and no permanent damage seems to have been done. So we all probably need to think about bringing in our tropical plants and digging up the non-hardy bulbs in the garden. Some plants do seem better able to handle the stress of being indoors than others. My hibiscus and jasmine do just fine, but the Princess Flower I tried to overwinter last year made it to about February then just died. I haven't had much luck with gardenias either. So I guess what I am saying is that as beautiful as some plants are it's just not worth the effort. Pitch them onto the compost pile with no regrets.

Another thing to be mindful of when bringing plants indoors, is what else you may be bringing in. Insects often lay their eggs on the undersides of leaves or in the soil and when you bring plants into a warm room the eggs will hatch and now you have an insect problem. There are many products on the market suitable for houseplants. Ann Larson from the Countryside greenhouse recommends cleaning the plant leaves with an all-purpose cleaning product we sell. You can also use systemic insecticides or sticky traps.

For my hibiscus and jasmine, I just drag them into my dining room, where they apparently get the right amount of sun because they do just fine. The hibiscus has even bloomed in there in January-- what a treat that is!

The canna are also easy to overwinter. I just let them die back in their containers and put them, container and all, into the the basement where it is cool and dry. Last year I did the same with the taro.

Other plants to overwinter:

Gladiolas-- When the foliage has died back, use a garden fork to lift them from the ground. Let them dry and clean the dirt off. Place them in a box with some peat moss or shavings and put them in a cool dark place. When the soil has warmed up in the spring you can plant them again. When you are digging you will find tiny bulblets--baby glads, if you will. Store them as well and replant in the spring. It will take a few years before they are big enough to bloom, but they will eventually.

Dahlias-- This is another garden favorite known for its large colorful blooms. These are actually tubers, and they can be over wintered as well. After the first frost, use a garden fork to lift the tubers. They can be quite large so be prepared. Let them dry for a day, and then cut off the stems, clean off the dirt and store in a box with peat moss or shavings in a cool dark place.

One of the benefits of overwinter bulbs and tubers is that you are saving older more productive tubers and the result the following year should be bigger blooms.