It’s zero degrees outside my office window and the indoor garden is thriving. Geraniums and petunias that I’m holding over until next year are still only a few inches tall after I cut them back hard. The amaryllis are still blooming one by one, the aloe continues to grow toward the ceiling, the desert roses are thinking of blooming (again), the lemons and limes are ripening, and the Christmas cactus is blooming. What is there to do except keep them watered and let them search for the brightest light from the window? Well, there are a multitude of indoor gardening projects you could be doing this time of year.
Search and Destroy All Pests
Every time you water your indoor plants, you should be inspecting for bugs. White flies and gnat flies are notorious for multiplying in the winter months. I’ve also had to control aphids and mealy bugs this time of year. The only real solution is to be a vigilant inspector.
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Some pests you can see right away because they like to hang around on any new growth at the top of plants. Other creepy-crawlies may be hiding on the underside of some of the lower leaves. Look for anything that isn’t green on leaves and stems. Once you find those pesky critters, you’ll want to isolate the plants as best you can.
When I found white flies on my petunias, I put them under lights downstairs. They are all alone now in the seed starting room keeping the worms company. When I found aphids on my hibiscus, I placed it on the kitchen table away from my other plants. Aphids tend to habituate themselves to only one plant species so you have less chance of them spreading. Putting the plant on my kitchen table was a way to remind myself to inspect it more often.
Sometimes you may need a magnifying glass to help see if they are bugs or something else. I have one almost identical to this one on Amazon. It’s small, foldable, and easy to keep in your pocket.
Unfortunately, my mealy bug infestation was not something I could keep ahead of. After trying to fight them for at least three years, I had to get drastic. About 4 years ago, I finally had to go through all my indoor plants and toss out every single one that had a mealy bug on it. I tossed every amaryllis, every African violet, and the citrus tree I was nurturing all summer. It was heartbreaking.
My remedy of choice for pretty much any bug infestation, is physical removal. I stay away from pesticides as much as I can. First I’ll cut away the most infested branches and put them in the garbage. That way it gets rid of most of the bugs before you even get started. It’s a time saver.
After removing the worst of the bugs, I’ll wipe down leaves and stems with a paper towel dabbed with rubbing alcohol. It works wonders as long as the number of bugs isn’t out of control. Ever since trying to conquer the mealy bugs, I keep a bottle of rubbing alcohol nearby. It can be rather satisfying to see the remnants of invaders on your paper towel. At the same time, you’ll be polishing the leaves. I’ve used alcohol on just about every plant I’ve ever had, and never had an issue.
The aphids on the hibiscus are now under control after several applications of rubbing alcohol. The last time I only found one aphid but I’m still keeping a close eye on it. I’ve noticed that one of the petunias in isolation is having issues again so I’ll have to make the decision to toss it soon. Don’t be afraid take a hard line, you’ll be glad you did in the long run.
So keep your eyes open and inspect carefully. All winter long.
Repotting
Winter is also a good time to repot those plants that have grown so large in the summer sunshine. Remember that sometimes you may want to repot and prune at the same time.
As you may have noticed with amaryllis, I prune roots and do a general cleanup when I repot. This year, since I never put my amaryllis bulbs in the ground, I had to repot every single one. Because roots can dull your good tools, I use inexpensive kitchen shears like the ones listed below from Amazon.
If you have plants that seem to drain water too quickly, it may be an indication they are severely rootbound and need a new pot. Right now my aloe and my Christmas cactus are showing signs they need a new home.
Some plants indicate they need a new pot when they have multiplied too much. African violets are notorious for growing multiple crowns that need to be separated. These same plants are also sensitive to mineral buildup and like to have new soil on an annual basis. If your violet has stopped thriving, you may want to consider a repotting project. It could revitalize it. My violets only need to be divided this time since both of them have two separate crowns.
Repotting is not an emergency situation, just remember that you can do a couple of plants one weekend and another next month. By the time this winter is over, I will probably have every one of my indoor plants in a new pot, though this doesn’t happen every winter.
Pruning
Some indoor plants need attention to keep them a reasonable size. Fruit trees, some succulents, and some plants that have become leggy in the dwindling light, are all candidates for a good “haircut.”
You’ve got to check out these trimming scissors we have in our new shop. They are some of the most comfortable and useful ones I’ve found.
Especially if you grow fruit trees indoors, there is no reason they need to reach the ceiling—unless you want them to. The lemon tree in my south-facing window is still bearing fruit so I’ll wait to harvest them all before I start pruning.
I’ll trim the branches back close to halfway and pay close attention to branches that are crossing over each other. The purpose is to create a more open structure that light can more easily penetrate.
At the beginning of winter, I’ll prune back my Desert roses as well. They can get very tall and gangly which isn’t as attractive as a thick trunk with shorter branches. I also choose this time because by the time summer rolls back around, they have produced more branches and are ready to soak up the summer sun. That is, if I’m brave enough to let them out in the harsh Montana weather.
Propagation
Winter is the perfect time for a propagation project, particularly if you like to hover over your plants.
Research the different methods of propagation. Seeds and cuttings can be fun to have going during December and January. It’s before the time you need to worry about vegetable starts, and the resulting plants will be ready to go outside when summer finally arrives.
For example, one of my amaryllis went to seed before I removed the stalk last summer. Why not see if they germinate? I also planted a few seeds from my Meyer lemon tree. If they germinate, the plants will make wonderful gifts to friends. (Looking for a seed starting kit? Try this one from Botanical Interests.)
Consider taking cuttings from plants that are getting too old or too big. Christmas cactus are a perfect example of this. My cactus was the only plant I saved from the mealy bugs all those years ago. Mostly because I could clean off the leaves easily before I placed them in soil.
Geraniums are another plant that I’ve propagated through cuttings quite easily. Instead of overwintering an entire plant, take a few cuttings and have a more vibrant, younger plant.
The only cuttings I have going this winter, though, are Japanese maples. Because I’m using my maples for bonsai material, I prune them quite often. As with most cuttings, I’ve had about half of the cuttings root. Once again, great gifts to friends, or an easy way to increase your inventory of plants.
If you are going to consider rooting stem cuttings, always be careful of plants that are patented. It is illegal to propagate those plant varieties.
Forcing Poinsettias
Another fun thing to do is winter over last year’s poinsettia and force it to “bloom.” OK, so they don’t bloom in the traditional sense since it is their leaves that actually turn color. But you can force them to change color with a little planning.
If you let them grow outdoors during the summer months, be sure to fertilize them to encourage some lush growth. Bring them inside in September and make sure that they get only 9-10 hours per day of light. I have a box that I cover to make sure no light gets in outside of those designated hours. It doesn’t take them long to start changing color. I got such a kick out of it the first time my poinsettias came back into color that I’ve been doing it ever since.
As the photos below show, the colors start out in interesting ways. Maybe only half of the leaf starts out changing color, but you will almost always see the color start on the leaves at the very top of the branches. It’s fun to see the different colors start to show themselves. Below are examples of red, pink, and a red “splash” pattern that is one of my favorites.
As it turned out, our days in Montana are so short that I didn’t need my dark box. Now I just keep the poinsettias in my window and treat them normally. When I do this, however, they turn color in January or February and not for Christmas. They also will not be quite as spectacular as what the commercial growers can achieve. That is due to the fact that those growers can create optimal growing conditions and it is the rare home gardener who can do that. I’m still appreciative of the color I get from those plants. I enjoy them so much that I’ve started to take my friends poinsettias that they would normally throw away. Now I have four plants that show their colors from late winter until summer.
Garden Planning
When the snow is swirling around your windows is the best time to start your garden journal for next year. Seed catalogs are coming in, too, and browsing through all the new varieties are a treat for every gardener.
Remember that you don’t have to do anything fancy, I use the Pages app on my iPad, but you can use a hard cover journal, a stack of papers stapled together, a notebook, or go higher tech and use one of those garden planning apps.
Our friends at Botanical Interests also have a free version you could check out below.
Be sure to check out my garden journal post so that you start thinking about all the different types of information you want to collect.
Gardening Tasks Abound
Now that you have a short list to get you started, share your indoor winter gardening projects in the comments below. Will you reorganize how you display your plants? Build a new table that perfectly fits your window? Build a potting bench? The possibilities are endless. Here’s hoping you complete all your projects by summer!