2011-11-17 / Editorial

The Island Garden Growing indoors during the winter

BY ROGER MARSHALL

Brrr! The cold winter months are coming, but there is no need to give up growing altogether. At this time of year you can simply take your gardening indoors. All you need is a sunny windowsill, a brightly lit area, or some space in your basement with a few grow lights.

You can start seeds under fluorescent lights, but to get the plants to grow larger you’ll need stronger lights. This usually means that you should invest in grow lights.

At a minimum you’ll need about 40 watts per square foot of light for at least 14 hours a day to get plants to grow indoors. If you can provide 60 to 80 watts of light over your grow area and some water and fertilizer, you’ll have the basis of a terrific indoor garden.

Of course, you’ll need to water your indoor garden. One way to do that is to set up a hydroponic system. It’s not that difficult and you don’t have to get really fancy. I use 10-foot plastic gutters as the basis for my vegetable growing hydroponic system. A five-gallon bucket serves as the reservoir and a fish tank water filter pump moves the water from the bucket to the top end of the water system. All I do is turn the pump on and leave it until the bucket is empty. Fifteen minutes later the water has circulated around the system and is dripping back into the bucket. The water gets turned on twice a day. Occasionally, I’ll turn it on a third time if the greenhouse has become quite hot, but that’s not often at this time of year.

Last winter I grew snow peas, beets and lettuce in the hydroponic gutters, and this year I plan to grow even more vegetables. The only problem is that the snow peas hang downwards instead of growing upwards and yields are slightly lower. Because my gutters hang on wires from the top of the greenhouse, there is always a danger that they will overturn if the plants become too top heavy, but I have not gone that far yet.

Another way to grow large plants is to keep them warm, well lit, and well watered in regular potting soil. I don’t recommend using soil from your yard. After a while it packs down and water has difficulty penetrating it, plus it can contain a lot of weed seeds. However, there are more trace nutrients in the soil from your yard so mixing up to 25 percent with potting soil and vermiculite or sand is not a bad idea, but make sure that the top layer of your pot is potting soil to control weeds.

If you grow indoor ornamental plants, make sure their leaves are clean. The leaves of many plants get dusty indoors and that affects the plants ability to photosynthesize. Keeping the leaves clean is one way to help your plant. Another way to help your indoor plant is not to overwater. The most common method to kill an indoor plant is to overwater, especially during winter when the plant’s respiration rates have slowed down.

To test whether your plant needs water, stick your finger in the potting soil. (If you cannot get your finger into the potting soil, it’s time to repot.) If your finger comes out damp, do not water. If it is dry, then water, but pour off any water that goes through the pot and into the holding tray under the plant. Only marsh plants like to sit in water and most ornamentals are not marsh plants.

Keep your ornamentals in an area where they will get moderate sunlight. If your plants are in an interior room where they will not get sunlight, you might want to shine a grow light on them to help them survive. Incidentally, plants in the home are good for you. They help absorb carbon dioxide and provide oxygen during the day when they are respiring. However, at night the reverse occurs and they give off carbon dioxide and absorb oxygen. Thus, you do not want to keep plants in your bedroom where you spend the night. You are best off keeping them in a sunny living area where you spend your days.

If you want to have paperwhite narcissus around at Christmastime, they’ll take about six to eight weeks to come into flower and now is the time to plant them. Similarly, Christmas cactus should be coming into its blooming stage. If it isn’t, give it a light dose of bloom fertilizer to help it on its way.

With little effort your indoor plants can survive the winter and be ready to be repotted in spring. In the meantime, you can enjoy their fragrance and benefits all winter long.

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