My last question about the room is: How much light is there in the room? Are there only large windows on the walls, or are there also skylights? Are there any electric lights to supplement the sunlight? If there aren’t skylights, there may not be enough light to grow vegetables once you move a few feet away from the windows. Indoor bright light is not the same thing as full sun. Winter days are shorter than summer days, so having lamps on timers that can start the lights early in the morning and run later in the evening may help.
Many types of houseplants will grow in sunrooms, but the vast majority of vegetable plants require full sun for most of the day, warm temperatures, and moist soil most of the time. If they don’t receive enough light or warm enough temperatures, they will grow slowly and not produce much fruit. If they dry out too often, they will drop their flowers and fruit.
If you are still thinking this will work, let’s move on to the pots. Most people will use flowerpots that are too small. A single tomato plant will need at least a pot the size of a five-gallon bucket. You might get two pepper plants in a pot that size. Any of the vines like zucchini or cucumber will need a large pot.
Normal potting soil for houseplants will work fine and it may include a small amount of fertilizer. Don’t use garden soil in the pots. A drainage hole in the pots will prevent too much water from remaining in the soil. The plants will not be growing as much as they would outdoors, so they won’t need as much fertilizer.
The best plant varieties to try would be smaller plants that are labeled “dwarf,” “compact,” or “determinate.” Determinate plants grow to a set size, stop growing, and then produce flowers and fruit. Indeterminate plants produce flowers and fruit over a long time and on a much larger plant. Look on the plant description for plants that bear crops sooner than others of their kind. A tomato that bears in 90 days is better than one that bears in 120 days. Indoors, they may take longer than usual to grow because of the lower light and lower temperatures, so faster fruit production may still get a crop this winter. A longer-bearing plant may not grow long enough to bear fruit.
Since this is your first attempt, try just a few kinds of crops and a few of each one. See what works best for you and expand next year.
