Buying a used greenhouse is an effective way to save substantial money while gaining the option of year-round gardening. When considering a potential greenhouse, there are four factors to keep in mind: size, materials, condition and price. Carefully weighing these factors will help you find the best greenhouse to suit both your gardening needs and budget.
When determining the size you need in a used greenhouse, it's usually a good idea to choose one that can adequately house all of your plants and have enough height for you to easily move around. Taller greenhouses are also beneficial, because they are easy to heat during colder months and ventilate in warmer ones. Many gardeners run into trouble later on, because they continually add more plants and eventually run out of space. They then end up adding upgrades that are often more expensive than simply purchasing a larger product initially. Therefore, choosing a slightly larger model than you need is usually a smart move.
Materials in a used greenhouse can differ dramatically, and there isn't really a single best option. The longest-lasting materials for the frame are aluminum and galvanized steel. These are ideal, because of their strength and ability to endure the elements. Plastic frames are usually a poor choice, because they are structurally weak and susceptible to heat loss.
When considering the covering, it's usually best to avoid glass, because it can break and can sometimes have difficulty retaining heat. Plastics such as polycarbonate and polyethylene film are typically your best choice, because they are shatter resistant and require minimal maintenance. Polycarbonate comes in varying thicknesses — single, double or triple — while polyethylene comes in single or double. It's usually best to choose the thickest covering possible, because it will reduce heat loss.
It's extremely important to only purchase a used greenhouse that is in good condition. Be sure to avoid buying anything with rust or cracks in either the frame or the covering. These are a sure sign of wear and tear and ultimately will result in a diminished lifespan, which means spending more money in the future on replacement parts. You should conduct a thorough investigation of the used greenhouse inside and out before making a purchase.
The final factor to influence your decision is the price. You can generally expect to pay anywhere from 25 percent to 70 percent off the normal retail value. It's usually a good idea to shop around and look at several greenhouses before making a final choice. Searching online or in classified ads for a used greenhouse can be an effective way to contrast and compare your options.