Greenhouses come in many different shapes and sizes depending on the garden, but one of the more popular types is the hoop greenhouse. The hoop greenhouse gets its name from the curved frames that create its hooplike structure. Other greenhouses often have an A-framed or traditionally roofed structure, but the hoop greenhouse looks more like a tunnel than a building. Gardeners enjoy using portable hoop greenhouses because of their ease of construction and flexibility in a garden or on a farm. A hoop greenhouse can be very tall and large enough to house an entire commercial nursery’s stock or just a few inches off the ground and small enough to provide protection for just a few plants.
The frame of a hoop greenhouse can be made of galvanized steel, PVC piping, or even wire. The framing material must be flexible enough to be bent into a half-hoop shape, like the frame on a covered wagon. Larger hoop houses can be anchored into a rectangular foundation frame, while smaller hoop houses made of wire can simply be anchored by burying the ends several inches (1 inch = 2.54 cm) into the ground. Frames are composed of several hoops that are evenly spaced a few feet apart for the length of the area needed. The covering for a hoop greenhouse can be made of thin plastic sheeting, heavy corrugated plastic or even lightweight fabric.
Hoop greenhouses for the backyard garden are often portable and can be made to cover the entire garden plot or just a single garden row. They are used to prevent plant shock from sudden cold temperatures, protect tender seedlings from wind and harsh weather, and to keep out insects and pests. Large-scale gardeners and nurseries selling plants for profit use hoop greenhouses because they are easy to set up, expand, and ventilate in warmer weather. Hoop greenhouses also tend to be cheaper to build than more permanent, roofed greenhouses because there is less framing material and hardware involved.
The main use for a hoop greenhouse is temperature regulation during the late winter and early spring or autumn months when temperatures can fluctuate wildly from day to day. The hoop design traps warm air inside the greenhouse and keeps temperatures consistent throughout the covered area. Often considered temporary, a hoop greenhouse can be uncovered, re-covered, depending on the daily temperature, and removed completely when the temperature is stabilized. The temporary nature of a hoop greenhouse also means that it is not as durable in heavy snows and extremely high winds as a permanent greenhouse structure.