For an ardent gardener a greenhouse is a dream come true. Tropical plants can be grown all year, seeds can be started in the middle of winter, and best of all, there is no end to gardening season. While many gardeners dream of having their own greenhouse, only a few ever actually achieve their dream and that's a pity. Even though building their own greenhouse is a significant amount of work, it isn't beyond the skills of many DIY'ers. If having your own greenhouse is one of your dreams, here's some thoughts on how you can actually achieve your goal.
Experienced gardeners say it’s best to start with the largest greenhouse you can fit into your yard, since whatever size you start with, you will quickly find it seems too small. Building a large greenhouse is easier and less expensive than trying to expand an existing building.
When deciding where to position your greenhouse keep the location of the sun in mind. Since you want the sun to shine into your greenhouse, locate it so it won't be shaded by an overhanging tree, your house, or any other building on your property.
Try to align your greenhouse so the longest side faces south, to maximize exposure to sunlight in the winter. The downside to this alignment is you may need to install shades to protect your plants from the heat of the summer sun.
Greenhouse kits are commonly available at building supply centers and on line in many sizes, shapes and different materials. Since a kit provides all the piece parts including doors and hinges, all designed to fit together, it will save you a lot of the cutting and measuring necessary to put your greenhouse together, However, kits are usually more expensive than a green house you build from scratch and you are still the person who will actually put the pieces together.
If you decide you would like to build your greenhouse from scratch, plans and designs are inexpensively available online or from home and garden centers. Building it yourself will also give you the option of choosing materials and you could even use recycled materials for much of the structure. All the necessary components (including windows, fans and watering systems) are commonly available at home and hardware stores so they are easy to include in your structure.
Some small home greenhouses are simply built on the ground without any foundation, however, for a more permanent structure some form of a foundation (gravel or concrete) is more appropriate.
Pea gravel provides an inexpensive floor and foundation for a home greenhouse. Simply remove any sod, dig down 3 or 4 inches and fill in the area with pea gravel. A pea gravel greenhouse floor won't get muddy or slippery when it's wet and will actually absorb any water spills, giving you a floor that is safe to walk on at all times.
For a large, permanent structure, a concrete floor/foundation is a better choice. Installing a concrete floor is a job you might consider contracting out, since it requires digging down about a foot, installing then packing three or four inches of gravel, topped by two inches of sand, and finally pouring a concrete slab--Altogether a lot of work and most of us don't have the digging, hauling and packing equipment necessary to do the job.