Smith County Horticulturist
Our average first freeze is in mid-November, but many tender plants can be injured at temperatures well above 32 degrees.
Some tropical plants used as bedding plants for outdoor color, like hibiscus and crotons, stop growing when it gets in the 50s, and can be injured in the lower 40s. If indoor space is at a premium, you might consider just letting the winter claim these plants and replace them next year with fresh plants from the nursery.
Lots of folks keep large houseplants outdoors during the summer. Usually the plants thrive in these conditions, putting on healthy new growth. With their increased size, they may not be able to fit in their usual spot inside, so you might need to do a little trimming.
Avoid drastic pruning, if possible, at this time of year. Some tropical plants will ooze sap from cuts, so let those dry a few days before bringing them in.
Taking steps now to prepare your plants for their trip indoors will ease the transition period and avoid a last-minute rush in the event of an early, unexpected cold snap.
Fertilize your plants to keep them growing and healthy, but begin cutting back on the frequency you feed your plants.
Prepare your plants for lower light levels by moving them now to areas in your yard or around the house that has the most shade.
The shadiest spots outdoors will probably be brighter than the brightest windows indoors. Keep them there for a week or two before moving them inside. Despite your efforts to acclimatize your plants to lower light levels, some might drop leaves anyway. Ficus benjamina, or weeping figs, are notorious for shedding leaves when moved.
Locate your plants near windows in the brightest rooms in the house. An extra source of light from a fluorescent fixture can help supplement the lower intensity of light your plants will endure during the winter months.
Other critters can sneak inside with your plants. Lizards, frogs, and toads are not uncommon. More than once, under the threat of a freeze, I have hastily hauled in plants in the late evening along with a wren that was happily sleeping in a hanging basket. Lizards and tree frogs are other animals that have enjoyed the unintended hospitality of a warm living room. That's another reason for not waiting until the last minute before bringing in plants before the first predicted freeze of winter.
Before bringing them in, you might also want to slip plants out of their pots and check the root ball. You don't want to bring a colony of fire or other kinds of ants inside. Pill bugs, snails, slugs, millipedes, roaches and earwigs are some of the other critters that can end up in your home.
Thoroughly water your plants a few days before bringing them indoors. Flood the pots until they no longer release air bubbles from the soil surface. This way the soil ball will be completely wetted. It is pretty hard to soak the soil of a potted plant indoors without making a mess.
You will need a saucer under your pots to catch excess water, but do not allow the bottom of the pot to sit in a puddle of water after watering. That is a good way to rot the roots and cause serious problems. Elevate the pot with a brick, or siphon out the water after the pot finishes draining.
Beware that water can condense on the outside bottom of clay saucers, causing damage to carpet or wood floors. I like to use wooden dollies on sturdy casters. These allow you to easily move large plants about, and keep saucers from directly contacting the flooring.
Keith Hansen is Smith County Horticulturist with the Texas A&M AgriLife Extension Service. His web page is http://EastTexasGardening.tamu.edu