In case this weekend wasn't your cue, let me be the first to say it: Bring the houseplants indoors. Fall finally arrived after days of 70-80 degree temps, but Terri Joiner, our tropicals buyer, informs us that, really, you start the plant migration in August.
I know what you're thinking. What about that gorgeous coleus in my summer container? Can I keep it alive all winter long indoors? First rule of plant migration: Decide who gets a spot in your winter confines. There are only so many windows to go round. (Hint: Take a snippet of the coleus and insert in water. It will root for next season.)
Let's divide this topic into houseplants and tender perennials. Example of tender perennials: That bromeilad you're dying to keep going. Example of houseplant: That philodendron that you can't kill.
Move Indoors: Late August is the best time to begin the trek back to the house, but first, a good shower, soak or some Neem Oil may be necessary. A summer outdoors means aphids, spidermites, mealybugs, ants, you name it. Clean-up the plants first by pruning off dead leaves, washing down pots, showering the plants and handpicking bugs. You can even submerge the pot underwater (using a bucket or big garbage bag) in an effort to remove soil infestations of critters. Neem Oil has an extra benefit of giving the leaves a glossy shine.
Repot? The best time to re-pot is in spring at the beginning of active growth. The plant migration causes stress and re-potting compounds that. Chances are good your houseplant grew during the summer and may have "tight shoes." That's okay so long as roots aren't coming out of the bottom of the pot, or there's no odor (due to poor drainage). Or, as in my case, the plants I took outdoors, I actually put into pots that won't come indoors, so it's necessary. Not optimal to be transplanting now, but if necessary go ahead. Here's a good link for how-to.
Fertilize: Not now. Your houseplants do need fertilizer when they're actively growing or flowering since they're in a controlled environment, but hold off during dormancy (fall/winter.)
Water: Consistency is key. You will water less initially and more once the heat comes on, but most important is a schedule. Do not allow water to stand in the plant tray after watering or as a technique to keep plants hydrated. Tip: take plants to the kitchen sink, water well, and let drain overnight. Return to their spot the next morning. Use round cork boards under pots to safeguard furniture. Rule of thumb: Limp leaves = too much water. Yellow leaves = too little water.
Light: Going from the bright light of outdoors (even if it was under shady trees, that light is brighter than indoor light) to the lesser light of indoors, can be challenging. Slowly allowing plants to get used to less light is optimal. Try to avoid grabbing the houseplant plant and putting it in its indoor spot. Move it every couple of weeks, diminishing its light with each move. (Tedious yes, but helpful.)
Pruning: As with our landscape plants, now is not the time to prune, but if it repotting is necessary, (plants have truly outgrown their pots, etc.) when you prune do not remove more than 1/3 of the plant size. However, you're best to wait until spring when plants are actively growing to prune and root prune your plants.
Tender perennials: (those plants you can't bear to part with but really aren't houseplants)
Experiment: I have a space under the house just barely big enough to stand up in. My cordylines, bougainvilleas, bromeliads, and a whole host of others spend their winter hibernating there. I rarely water (maybe once a month?) but do add a grow light that hangs over them for the season. The temperature stays around 50 degrees and many have lived through the winter but many have died (Kimberly Queen ferns just don't make it for me). It's trial and error, for sure. In February, I start watering a little more regularly (2x a month) and by mid-March, I have brought them into the garage where the temperature is still cool but warmer. By the first of April, they're back in my garden, though many have spent a few nights in my kitchen if we have a spring frost.
If you're thinking that you're the bad plant parent because we just had our first frost, and all your lovely plants are outside, no worries, better late than not at all. Today is the day.
Cinthia Milner is the garden coach, blog writer, and outside sales staff for BB Barns Garden Center.
BB Barns serves all of Western North Carolina, upstate South Carolina, and Tennessee.