Below are five key questions that will help you decide if you need a greenhouse:
Would you like to start more plants from seed with more success?
If you're a seed starter, you know that half the struggle is getting those seedlings plenty of light so they grow fast, stocky, and strong. Most indoor grow lights are barely adequate. A greenhouse provides as much light as the sun does.
Do you want to get your cuttings off to a better start?
A greenhouse allows you to start more cuttings earlier and have better results. You'll have larger, sturdier plants that will take off faster with less pampering come warmer weather.
Do you want to save money by overwintering tender plants?
Some of our favorite plants are marginally hardy. A mini-greenhouse, depending on the plant and your climate, allows you to gain approximately two hardiness zones if you grow the plant in a pot and overwinter it in the greenhouse. In colder climates, it's a resourceful way to overwinter prized plants such as rosemary, fig trees, gardenias, jasmine, and citrus.
Do you crave more veggies earlier in the season?
Some greenhouses can be constructed with raised beds or set right on the soil. This allows you to start tomatoes and other produce weeks and even months earlier. Then, when temperatures are warm enough, remove the mini-greenhouse. (Charley's Greenhouse and Garden, for example, makes a special mini-greenhouse tailored for growing tomatoes right in the ground.)
Do you enjoy forcing bulbs in winter?
If you plant spring-blooming bulbs in fall for forcing into early bloom during winter, a greenhouse may be helpful, depending on your climate. Keep it at refrigerator-like temperatures (40°F to 55°F) for at least 12 weeks to let the bulbs sprout. Then bring them indoors, where they'll grow and bloom.