Growing Herbs Indoors Over Winter
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Growing Herbs Indoors Over Winter
Q. Laura in Albany New York writes: "I'm a long-time perennial gardener and this summer I also built a raised bed for an herb garden. Boy have I been missing out! I love cooking with fresh herbs so much that I am determined to have an indoor herb garden this winter. Here in Albany our winters can be long and cold - and fresh herbs can be scarce.
"I have a section of my finished basement that I would like to transform into an indoor greenhouse. Can you give a newbie like me some tips on how to set up my indoor garden for success? Things like heat, water requirements, etc.? I ordered a bunch of herb plants from an organic growers' exchange that will be delivered to me in mid-September. I'm also trying my hand at "rooting" some cuttings in water from my existing herb plants (rosemary, tarragon, oregano, mint...) to see if I can propagate some of my own plants for the indoors. Thanks for all the great shows. I listen to them on the weekends in the winter while the snow is piling up and imagine myself outside in the sunshine gardening!"
A. I think you have a doable idea, Laura. A lot of people think they can duplicate a summer garden indoors over winter with plants that get big fast--like tomatoes and cukes. Smaller, less temperamental plants like herbs are a much better choice--especially when you're trying this for the first time.
Now: Rooting plants in water is really cool; people love seeing those long white roots filling up a jelly jar--but those weak roots can't survive the transition to soil. To do this correctly, cut several sections of new growth from each plant. Have containers and a high-quality organic potting soil ready. Fill the containers with the mix, let them sit in a sink with a couple inches of water in it for an hour, drain, and then use a pencil to make 'planting holes'--don't force the cuttings down into the soil. Remove any leaves that will be below the soil line, drop them into the holes, gently fill in the holes with more soil, mist the cuttings, and cover the whole Schmiege loosely with a plastic bag. Mist daily, and with a little luck the cuttings will take root.
Or, since you're in Albany, just dig up the rosemary, oregano and other plants that would otherwise die over the winter, pot them up and bring them inside. Spray them with fiercely sharp streams of water several times after they're potted but before they come inside to get rid of any hitchhiking pests.
OK--now the indoor greenhouse delusion---eh, I meant "instruction", not delusion!
A finished basement sounds cozy--a LOT cozier than the Middle Ages-era cellar I'm stuck with (was everyone under five foot five back in the 1800s? Or did they just not know how to measure??). If the temp in your basement ranges from the high sixties to the low seventies, you should be fine. But don't locate the set-up right near a door to the outside, a window that will get freezing cold at night or a heater.
Brass tacks: Get one or two of those big folding plastic tables; plastic because they're gonna get wet; folding because you'll probably want to store them over the seven weeks you upstate New Yorkers call "summer". Big plastic containers for the plants as well. Yes, terra cotta looks really nice, but it wicks its moisture into the air and is a bear to keep watered--especially indoors over the winter, when humidity typically runs away to hide.
If you want to try this on a small scale, start with shop lights that hold two four-foot long tubes. If you want to go all in, get fixtures that hold FOUR four-foot long tubes each. (That's what I use to start my tomato and pepper seedlings indoors--they give off a lot of light.)
Now comes your MacGyver moment. You want the tops of your plants to always be as close as possible to the tubes--an inch away or less. So either hang the lights on chains that you can use to raise them up or start out on top of those books you will never read and remove books as the plants grow taller. (I use the 'book roulette' method.) Most sources will tell you to put the lights on a timer and have them go off for eight hours every night. I can never find my darn timers in March so most years I leave the lights on 24/7 and everything works out great.
Watering: You want the roots to be able to dry out between waterings. Everyone's indoor humidity is different, so go by the weight of your pots; if they feel light, water; if they feel heavy, walk away Renee.
Food: Herbs are not heavy feeders, so a dilute solution of liquid organic fertilizer once every six weeks should be plenty. If you prefer granular, make it about a quarter-cup per plant, and make sure you have a bag of compost handy, as any granular fertilizer should be covered with compost or soil to make it more available to the plants.
Good luck, grasshopper!