While the weather outside is frightful

Outdoors it’s winter, but plants still grow and even flower indoors, despite short days. During winter, I try to nurture houseplants in a sustainable way by limiting turnover, minimizing use of materials with high carbon cost, and carrying over outdoor plants that can make it through the winter next to a window or under lights.

Geraniums and succulents making it through the winter under a grow light

    Some of my houseplants may be older than my children. I can’t resist treating them like pets and keeping them even when they aren’t beautiful. This winter I’ve added some pretty young variegated ivy and a fern to the collection. 

Variegated ivy can thrive indoors and out

I’ve had good luck transplanting low-light selections like these in spring to a large box planter in a shady area. This way I can enjoy their foliage through both the winter and the summer. The fern will succumb to next fall's frost, but the ivy may tough it out and become a perennial.

    Winter blooms of African violets, orchids, paperwhite narcissi, and amaryllis will add some welcome color to this mostly green scene.

African violets blooming in February

    I also rooted cuttings from some of the neonicotinoid-free geraniums, coleus, begonias, and rosemary that I bought last spring to plant in summer containers.

 

A confused geranium blooming this week

It was difficult to find plants that hadn’t been sprayed with the pollinator-toxic insecticides. I’ll be able to use the old plants’ descendants next year and avoid the search for untreated plants. The youngsters aren’t going to get me into House Beautiful, but I think they look cheery under a grow light in the kitchen/family room. They’re located where I can’t miss seeing them, so I notice when they need care.

    By recycling plants from last summer, I avoid the carbon cost of new plants. This can be considerable, because they often travel to local garden centers from remote parts of the country and the globe. I also reuse the plastic pots and six-packs that my plant purchases came in. 

Ready for starting seeds in early spring

Washing the soil out of these and storing them in the basement is a winter activity. Like the indoor bulbs, cuttings from summer plants are grown in homemade peat-free potting mix. By using this growing medium instead of commercial potting mix, I spare the peat bogs, which sequester much of the world’s soil carbon.

    I’ve long had a fantasy of enclosing a small porch at the side of the house in glass to use as a greenhouse or conservatory. 

The conservatory at Tower Hill Botanic Garden

In addition to the cost, a concern that holds me back is how I’d cope with infestations and plant diseases indoors. The greenhouse manager at the Arnold Arboretum once told me that they emptied the greenhouse once a year to clean it thoroughly and spray it with diluted chlorine bleach. The prospect of donning a hazmat suit and mask to spray an indoor space with chlorine or other toxic pesticides cooled my enthusiasm for a greenhouse attached to our living space.

    Unlike the Arboretum staff, I’m not growing irreplaceable specimens. If indoor plants get sick or attract insects, they’ll find themselves filling another sustainable role—as compost.

Happy holidays, inside or out!