Before attempting to grow plants in the north it is important to know a couple of rules. Most garden plants need 12 to 14 hours of sunlight to be heavy producers. Plants without this much light can grow long and spindly. Don’t let this stop you though.
Over the past 12 years we have experimented with a number of different plants. The first plants we grew were canna bulbs and bamboo. This combination might have worked well if we had been in the building year round but without adding water to the wetlands from the shower or sinks the bamboo died. The cannas grew 14 feet tall, bloomed year round, and still thrive in the bedroom wetland.
One year I planted several native Ohio plants plus stuck two avocado pits into the far end of the living room wetland. When we returned three years later there was a jungle where there had been nothing. Some of the plants had spread into the living room and kitchen. The avocado trees were pushing up against the ceiling as if they were trying to force their way out.
Over time I learned to prune back the trees in the winter to give sunlight, and let them go wild in the summer to make shade when the sun was in the west. The banana plants took three years to grow tall enough to provide shade with their giant leaves, and have not yet produced fruit yet. They do send up baby shoots as if to say they are thinking about reproducing with a stalk of tiny sweet bananas.
Before we lived in the house fulltime we used the bedroom wetlands to hold trays of seedlings awaiting life in the outside garden. We used grow lights to nudge the little plants along until the outside garden was ready to receive them. Today I put the big potted poinsettias in there from September until Thanksgiving, when they begin to set their brackets for a beautiful display during the winter holidays. Visitors can’t believe that I can get poinsettias to “bloom”, but I believe it is the combination of light and warmth and coolness in the wetland that enables them to be so showy.
Wetlands are great places to grow annuals, like citronella geraniums, basil, mint, and rosemary. Calla lilies, castor bean and thyme do well. The main thing is to experiment, and not to be afraid to keep the plants trimmed back so that they put more effort into setting fruit and leaves, and not so much in creating long stems.
Weeds are not usually a problem, but don’t let them get established. Use organic fertilizers such as llama poo, which can be sterilized in a solar oven or in the microwave. If you don’t sterilize the fertilizer you might end up with insects and bacteria that are harmful to the indoor garden. Once these pests are established it is a challenge to get rid of them. If you do have an infestation just use some diatomaceous earth #2 food grade to dust the plants. Some insects are helpful though – the main thing is to create a balance.
For the past two winters we’ve grown tomatoes in one end of the wetland. The one plant is established in July so that it has plenty of time to grow. Don’t use just any tomato plant though. Heirloom varieties enable you to not only grow delicious tomatoes, but also to cut pieces from them called “slips” that you can root and plant in your spring garden. Last year the plant in the living room wetland produced salad tomatoes from the first of March until we had them in the garden. We pollinated the plant by shaking the plant whenever we noticed a new cluster of tiny yellow blooms. The plants started from that one huge wetland plant created an endless supply of salad tomatoes until frost.
The main thing to remember about growing in the wetlands is that the intensity of light is somewhat reduced and you don’t want to introduce the wrong kinds of insects or bacteria. Even if you forget these rules you will find that experimenting for your area will provide you with many enjoyable experiences, and some beautiful indoor greenery. You’ll be able to stand back and smile when your visitors go on and on about your indoor plants.
Annie Warmke is the contractor for the first Earthship built east of the Mississippi and co-owns Blue Rock Station, a sustainable living center in southeastern Ohio. She is a longtime friend of Earthship Biotecture, Sustainable Communities Initiatives in Scotland, and promotes their work throughout the world.