Ask a Master Gardener
Bringing Plants Indoors
10/26/24
At some point summer temperatures are going to end…at least we think so. At that point we’ll need to bring our summer tropicals indoors, or at least those plants we want to save until next year. Hibiscus is one I think of. There are both tropical and hardy versions of hibiscus. The hardy ones are usually good outdoors over the winter, but if you want to save those tropical ones, they will need to spend the winter in your garage or someplace appropriate.
To understand which plants need to come indoors, we need to talk about growing zones. The USDA publishes information that divides the country into various growing zones. This information has to do with the average coldest temperatures a particular region gets. Historically, we have been in Zone 7A but we are now in Zone 7B. The difference between these two is how cold it is expected to get during the winter. The average lows for 7A are 0 to 5 degrees while the average for 7B is 5 to 10 degrees. So, we have warmed up a little bit…in theory. These zones identifiers help you make purchasing decisions as well as let you know what you need to bring plants in if you want to save them. However, we all know that winter temperatures are rarely average. Typically, they are above or below or both. And some of us remember those subzero days that seem to linger which feels like Zone 5 territory, eliminating plants that are usually good here, like crapemytles.
So, if you have plants that need to come in, be sure to wash them well with a hose first. This will help to wash off any pests and clean up the plant before it comes inside.
Insects tend to go dormant in cold weather and you may have some dormant insects in the soil of your plant. Bringing the plant in might wake them up so to speak, so having a little insecticidal soap or neem oil on hand to treat your plants should that occur is a good idea.
Naturally, your plants would prefer a nice sunny place, but they can get by with a grow light. Luckily grow lights have gotten a lot less expensive in recent years and those LED grow lights seem to last forever.
You’ll also need to find them a place that is warm and free of cold drafts. Windows are good locations, just keep the leaves away from the glass since that glass can get cold in the winter.
And last but not least, keep your plants watered. Watering once a week is usually sufficient, but some plants start to get droopy if you let them go a week without water. They will let you know when they are thirsty. There are also inexpensive soil moisture meters if you want to eliminate the guesswork.
Also, don’t be surprised if your plant drops a few leaves when you bring it in. This is usually not cause for concern, just your plants adjusting to their new home. Good luck!
You can get answers to all your gardening questions by calling the Tulsa Master Gardeners Help Line at 918-746-3701, dropping by our Diagnostic Center at 4116 E. 15th Street, or by emailing us at mg@tulsamastergardeners.org. Photo: Tom Ingram