Part 1: Bringing in Your Plants; not Pests and Part 2: Helping Pepper Plants Thrive Over Winter

Welcome to You Bet Your Garden. I'm your host with the most, Mike McGrath. There will not be an "In the News" segment this week, because I want to use that time to hammer down the rules for bringing house plants indoors for the winter before the weather gets overly chilly. We're calling it:

Part 1: Bringing in Your Plants; not Pests

Liz in the fabled Egg Harbor section of New Jersey writes: I have several tropical hibiscus that I want to bring into my sunroom for the winter. But I'm afraid that I'll also bring in some unwanted pests, like whiteflies, spider mites, and mealy bugs. Besides giving the plants a good shower with a garden hose, what can you suggest that I spray or add to the soil to prevent infestation?

Nothing.

No outside inputs are needed here; and {quote} "a good shower with a garden hose" would help the pests, not the plants. Note: Almost every technique I'm about to suggest applies to almost every houseplant coming in for the winter.

First, don't delay. Warm weather time is ending, and nighttime cold is ready to roll in and severely weaken any tropical plants left outdoors. (At least that's generally been the climactic case; your results may vary.) In addition, tropical hibiscus is one of the least cold hardy plants, so don't roll the dice. It should be the last plant to go outdoors in late Spring/early summer and the first to come back inside well before chilly nights appear. A light frost would probably kill it, and temps below fifty will make it very unhappy.

You are correct to worry about hitchhiking pests, but a shower from a hose would only make them happy. Removing aphids and thrips (which are the most common pests of indoor hibiscus) requires a hose nozzle or hand held sprayer that you can adjust to a deadly laser-like setting to blast the rats off. Be sure to hit the undersides of the leaves, where any whiteflies and mealybugs will be hiding.

Let the plants sit for a few days and then do it again, examining both sides of the leaves. If you see or feel something amiss, rub it off with your finger or a Q-Tip saturated with rubbing alcohol. Take your time and do this well; a little prevention now will be much more effective than trying to come up with a cure later.

Once indoors, place hibiscus in the brightest INDIRECT light you can manage that isn't near a poorly insulated window or hot air source like a heating vent.

Then, don't let the plant dry out or drown.

If the pot feels light, it's time to water. If it feels heavy, the soil is already saturated and you should walk away. Using a humidifier to counteract the dry indoor air of winter will keep you and your plants happy and make spider mites miserable, as dry air provides their perfect environment. Mist plants every other day or so to keep them away.

And finally, have a bunch of yellow sticky traps handy and place a couple in each pot right away to catch any flying pests that you missed. If the traps start to catch a lot of them, repeat the blasting with sharp streams of water in a tub or shower.

And now....

Part 2: Helping Pepper Plants Thrive Over Winter

Q. Stew in Lambertville New Jersey writes: "I took your advice and brought my pepper plant indoors last fall and put it in a South-facing window. It survived the winter, then I put it back out in May. It had three buds at the time, which bloomed and started to become fruit. The squirrels got two of them, but the real problem is that it didn't bloom again until the first week in September, and now has six buds. What is going on?

A. In a word, climate change. The weather emergencies in many areas this Spring and Summer were crazy, with some areas enduring heavy rain while nearby communities were bone dry. But sooner or later, everybody got flooded or battled long droughts; either of which can cause peppers to hit the pause button. It sounds like our listeners weather became 'normal' enough recently to re-start production.

Luckily, drought can be battled with more frequent and longer waterings. My rule of one inch of water a week only applies to a normal growing season, which we did not have. In such dry situations, I pretty much double down, watering deeply (using a standard impact sprinkler) for several hours in the morning every three or four days, depending on the humidity and dewpoint.

Low humidity makes this chore much more difficult. It's tough to give your plants the moisture they crave when dry air sucks it right back out. Watering in the morning, before the sun hits the garden can be a big help. (The ideal time sequence is a five or six am start, ending at eight or nine.)

But there ain't much you can do when your neighbor is building an ark. Most plants can recover from five or six days without rain, but really struggle if they have to endure the kind of rainstorms they show on the national news.

And climate change has caused more heat and drought as well as periods of Biblical rain. In either case, people growing in raised beds outdoors have a huge advantage, as those beds retain water during dry times, and have essential drainage during floods. On the other hand, Flat Earth gardeners are at a great disadvantage as their compacted soil can't absorb water well, so they suffer more during dry spells. (Wet spells too if the garden becomes cursed with standing water.)

Anyway, I'm guessing that our Lambertville listener is currently growing his pepper plant in a container, which makes it easy to move indoors.

(If you're unfortunate enough to have a pepper planted in the garden proper, wait until the sun goes down (to lower heat stress) and pot it up in a good size container containing a mix of compost and organic potting soil (not one whose label implies miracles). Then water the container by sitting it in a bathtub, sink or galvanized tub containing enough water to let the plant hydrate via the container's drainage holes.

After an hour or two, lift it out and note the weight of the container. A fully saturated pot should feel at least twice as heavy compared to before it was watered. Don't water heavy plants. But if it's light, it needs water. (Don't judge water needs by sticking your finger in the soil or other such nonsense; container weight is better than a moisture meter.)

Move the saturated pot to a shady spot for a couple of days to prevent transplant shock. Then move it to an area with morning sun and afternoon shade; and start checking the nighttime low temps in your area. If the seven-day forecast includes any nights in the forties, bring it inside. Same with your house plants. These are tropicals that have no sense of humor about cold nights.

Bring the container to a sink or tub and spray every part of the plant with SHARP streams of water to remove the unseen aphids that LOVE sucking pepper parts. Wait a couple of hours, then do it again.

Then select a proper place indoors, that is NOT a so-called sunny windowsill. Touch the glass on a cold night and you'll know why. Plus, the hours of sunlight are rapidly diminishing, AND the sun is now at a bad angle for photosynthesis.

A true, well-insulated conservatory-style bay window facing South or East that's not near a heat source like a radiator or hot air vent should work well. If your house is seriously dry over winter, mist the plant with plain water and check the weight every other day.

But most people don't have such a place, so locate a spot where you can hang a plant light. Don't use incandescent bulbs, which will dry things out. A fixture containing two fat 24 inch fluorescent tubes will easily accommodate two plants. Position those plants directly underneath, an inch or two away from the bulbs. Same with a look alike LED fixture. Either way, your plant(s) should not only survive the winter but flower and fruit for you indoors.

Don't take it back outside in the Spring until nighttime temps are reliably in the fifties or warmer. And don't directly feed Evil Squirrels or put up a seed feeder for birds. If you do either, future Squirrel attacks will be your fault.