Daytime temperatures are still in the 70s but watch those night temperatures. The 10-day forecast shows temps well below 55 degrees. That means, bring the houseplants that have enjoyed a summer outdoors indoors now. Tropical plant migration is an August chore, but if you missed that deadline, today is the day. Mark your calendars for next August (late August, early September) as a reminder; otherwise, next year will be a repeat of grabbing plants and rushing them indoors before nightfall and frost.

Note: If you’re wondering which pots to bring indoors for winter storage, read here.

The first rule of plant migration

Decide who gets a spot in your winter confines. There are only so many windows to go round. Don’t waste time on plants that are inexpensive and proliferate. Coleus, for example, is a relatively cheap plant that grows large in one season. Consider that an annual and purchase it again in the spring. Some outdoor plants like Kimberly Queen ferns aren’t cheap, but they grow slowly, and I prefer them large when they go into the garden. I experimented one winter by storing Kimberly Queens in the garage and bringing them out in spring. It took ages to get any size on them. I want my ferns to be an instant happy in the garden so, those are purchased again in spring. Unhealthy plants aren’t going to perform better indoors, so rule those out. Don’t be sentimental about your choices. Cull now to save yourself the trouble in January.

Let’s divide this topic into houseplants and tender perennials. Example of tender perennials: That bromeliad you’re dying to keep alive until next spring. Example of houseplant: That philodendron that you can’t kill.

‘Red Kiss’ Rex begonia. Rex begonias love filtered light and I add them to the shade garden. They go into a spare room where the heat is turned off and the morning light is filters through. I water every other week, very lightly in the kitchen sink, letting them drain over night.

Houseplants 

Move Indoors:  But first, a good shower, soak or some Neem Oil may be necessary. A summer outdoors means aphids, spider mites, 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.   

Re-pot? 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). It isn’t optimal to transplant now, but if necessary go ahead. Here’s a good link for how-to.    

Succulents can be brought indoors. They need a very sunny window. Allow the soil to dry out between waterings, and do not fertilize until spring.

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 critical. You will water less initially and more once the heat comes on, but most importantly is a schedule. Do not allow water to stand in the plant tray after watering or as a technique to keep plants hydrated. 

Tip: When buying houseplants, don’t transplant them but leave them in their nursery pots. Instead, drop them into decorative cachepots that have no drainage. Take the nursery pot to the kitchen sink or in the bathtub to water and leave, allowing to drain for 24 hours. Use round cork boards under cachepots to safeguard the furniture. (A cachepot is a French word for a planter, but we use it to describe planters that remain indoors.)

Rule of thumb: Limp leaves = too much water. Yellow leaves = too little water. 

Light: Going from the bright light of outdoors 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.)

Cold Nights: As you’re transitioning the plants, be sure to protect from nights that reach below 55 degrees. The plant may live in those temperatures but, it does stress the plant. Bringing it indoors is already stressful to the plant, so be sure to keep an eye on the weather.

Philodendrons are a must have plant. They’re indestructible, making the transition from outdoors to in or indoors to out with relative ease.

Pruning: As with our landscape plants, now is not the time to prune, but if 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 aren’t houseplants)

Experiment: I have 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. 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 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. I don’t stress over these plants. If they make it they make it.

A closed-off bedroom that gets dim light works just as well. Make sure heat vent is shut off, and plants are getting filtered light, not bright or direct sunlight. Water, but don’t drench the plants until February when you start removing them from their winter spot.

Bromeilads are easy to keep alive in the garage, or inside the house. If keeping them inside, just keep their “cups” full. In the garage, just ignore and wait for next season

If you’re thinking that you’re the bad plant parent because you’ve forgotten all about your lovely plants outside, no worries, better late than not at all. Today is the day.

Cinthia Milner is the garden coach and blog writer for B.B.Barns.

BB Barns serves all of Western North Carolina, upstate South Carolina, and Tennessee.