Care For And Inspect Houseplants Before Their Winter Dormancy

My annual admonition that it’s time to get your houseplants inspected, protected and back indoors is late this year, but it’s here. Well, it’s time. It’s also time to hit the garden centers to get stocked up on those plants that will delight you and your indoor spaces. Come January through early March, you’ll be very happy when they’re giving you eye candy and even some great scents.

First though, your existing houseplants. Mine have suffered for the past few months as my attention has been focused on the outdoor gardens. While I have no insect issues on my plants, I have managed to over-neglect a few and have had to trash them. Some need renovation and rejuvenation so they can revive by wintertime. Even the ones that have stayed indoors will get outside on a mild day to get their semi-annual showers, washing off dust and grime while inspecting for this bug and that.

Even your largest houseplants that are manageable should go outside on a mild day and be washed. This can be done with just plain room temperature water or with a tiny bit of dishwashing liquid mixed in. Sponge them, spray them (top to bottom, not bottom to top) and give them a good but gentle cleaning. Don’t do this in direct sun though as they may get burned. Also, allow them to dry before they come back indoors.

The process is more critical to any plants that have been outdoors for several months. These will pick up even more dust but there’s also the chance that a few insects may have visited or set up home. Inspect both surfaces of the foliage as well as the stems and branches. Look for scales that will probably be like small brown or tan bumps that don’t move and check for aphids. The aphids will move as you get close to them.

Aphids can easily be washed off. Scale is much more difficult, and if you find some then you need to isolate that plant once it goes back indoors. Make very certain that plants with any scale don’t come into contact with other plants. Aphids can fly, but rarely do indoors, and are social insects so they usually occur in groups around buds, flowers and fast-growing shoot tips. Scale will need several oil treatments so if you do find scale please read up or ask for help.

Slugs may have invaded plants that went outdoors, and several types of beetles may have entered through the drain holes in the pots. Check the pot bottom for slugs, and gently remove the plant from the pot to look for signs of beetles or other mysteries. I learned how important this step is when I had one plant that had something eating the leaf margins for weeks and weeks well into December. Turns out it was a beetle living in the soil that would only emerge at night. It was discovered when the plant was de-potted for an inspection when I got suspicious.

When plants come back into the home try to recreate the lighting that the plant has outdoors. It’s probably OK to give it more light as the light quality will decrease once inside but be careful not to reduce the light too much as the plant will only slowly let you know how unhappy it is months from now.

Unless you have flowering plants inside, start to cut back on feeding houseplants. It doesn’t mean go cold turkey. Rather, use a strategy like this: If you’ve been feeding 1 tablespoon of fertilizer every week cut that in half and then in half again in November so the plant is only getting a quarter of the summer fertilizer dose when we get into the cold and dark days of winter. Then in late February or March, gradually start to increase the feeding amount.

It’s much better to feed at ever watering than once a week or every two weeks. Just dilute the fertilizer amount to the fraction needed for continuous feeding. If the instructions call for a teaspoon every month and you think you’ll be watering the plant four times a month, then cut the fertilizer amount to a quarter teaspoon every watering. Get the idea? This avoids peaks and valleys in the available fertilizer you’re giving the plant.

When bringing plants back indoors be careful with the temperatures. Plants like Fatsia japonica will drop their leaves if there’s a sudden cooling down, and then the plant is essentially lost.

This is not a great time for repotting. Remember the plants are starting to go somewhat dormant as we cool down and lose hours of daytime lighting. If repotting can wait, spring is best. Keep in mind also that as the plant slows down so does its uptake of water. You can always add water but you can’t take it away. During the cooler months overwatering often means unhappy plants as the slowly growing plant can’t take the moisture out of the soil. Again, remember, you can always add more water. However, a water-logged pot can be challenging to dry out.

As for new houseplants, here are a few tips: Smaller plants that you buy young and let “grow in” will do much better than larger plants that are established and may have been in ideal greenhouse situations for months or longer. Smaller plants are also less expensive and may give you the opportunity to try more varieties and find some new plants that will do particularly well for you. Always isolate new plants when you get them home, and give yourself a few weeks to watch the stems and leaves for any insect issues.

So many plants and types to choose from, and often they will only come with a simple label and the most basic of care instructions. Use your smartphone when shopping and try to get a profile of the plant you’re interested in.

You might find 20, 30 or even more types of plants at some garden centers. These are going to be the most common ones. If you really want a nice or challenging indoor plant collection then shop online at a place like Logee’s Greenhouses (logees.com) where you’ll find hundreds of plants to choose from. Since they’re in Connecticut, most of their plants can get here in a day, and shipping should be no problem through the end of October.

Most of us will stick to the various forms of Ficus, Dracaenas, Dieffenbachias and the usual standards. These are all fine but keep in mind that there are now over a dozen varieties of Ficus available and some do better than others. Ficus benjamina is a standard (also known as the weeping fig) but sudden changes or being pot bound can cause leaf drop. Ficus decora and Ficus picta are the wide-leaved varieties with green, dark maroon and even variegated foliage with whites, creams and pinks. All the Ficus, including the trendy fiddle leaf Ficus, will grow tall and will need to be managed. The same holds true for the Dracaenas and Dieffenbachias.

By all means, try some orchids as well. Some are very inexpensive and nearly disposable — but learn about the ones you buy. Some are very easy and yes, they will rebloom. Better yet, if you’re new to orchids ask for help at one of our better garden centers. Selections now are great but get very thin as we get close to Thanksgiving.

If it’s indoor fruits you’re after, then look for potted lemons like the Meyer types. There are also some limes being marketed now. These plants have glossy green leaves, and when in flower the scents are just magnificent. They need to have bright light and a 10-degree day/night temperature change to induce flowering. A sunroom could be perfect. They will get large but aren’t fast growers, and the fruits are edible. No, you can’t grow bananas or pineapples indoors, at least not ones that will fruit. Growing an avocado from a pit or a pineapple from a cut-off top can be fun and interesting for the kids, but you won’t get an avocado or a pineapple from your efforts.

There are miniature roses that you can experiment with indoors, but they can be challenging in terms of disease in insect issues. How about African violets? Easy as long as you don’t overwater or get the leaves wet, and most will flower for months on end in low light. In the same family, there are the Episcias, but these are challenging and do best in a terrarium. Some have spectacular foliage that’s only outdone by their striking flowers.

Again, if you’re an adventurer, buy smaller plants and experiment. Find out what works for you, and if you have failures, you’ve only lost five or six bucks and your successes will lead to many, many more. I find indoor gardening very therapeutic when it’s 20 degrees outdoors. By then though, it’s way too late to be bringing plants home. Try some new plants and of course, keep growing.