Many of us use their backyards for more practical purposes than keeping a lawn. And what could be more practical than growing some fresh veggies on your own? Depending on where exactly you live, the growing season can be long or short. For those of us living in places with shorter season, there is still a solution to extend it - build a greenhouse.
Building a greenhouse is usually easier than building a shed and can be cheaper, or not. If you build a large greenhouse with glass, isolation and steel construction the cost can be far higher than the cost of a decent wooden or metal shed. But these greenhouses aren't the only possibility.
Types of Greenhouses
There are a lot of typizations of greenhouses. I don't want to get scientific here, this is not a textbook. Let's focus on the main types of greenhouses that interested as homeowners and mostly as DIY guys. So we'll do our own typization here.
These are all greenhouses where you can go inside yourself to start your seeds or grow your produce. Obviously such a construction will have minimum height of about 2 meters and be at least 2-3 m long and wide. In most cases these are more useful as they can help you grow high plants like tomatoes, cucumbers and so on.
The problem with them is of course you need more space in your garden and more material to build them.
Small Greenhouses: Hoop Houses and Cold Frames
Small greenhouses are those where you can't enter inside. They are either too small generally or at least not high enough, like the short hoophouses. Such greenhouses are suitable for starting seeds or for growing vegetables that are not tall. For example many gardeners grow green onions in loophouses or cold frames during winter. You can also grow all kind of leafy vegetables like kale, spinach, lettuce, and so on.
The main advantage is that they are simple constructions and easy to make. Small hoop tunnels are often sold at hobby stores for very little money and you don't even need to make them. Cold frames can be made of scrap wood and windows.
By The Material: Wooden, Steel or Plastic
All greenhouses need some kind of supporting construction. Usually you'll find wood used on the older ones. Wood is affordable and easier to work with. It rots over time, shrinks and expands under the sun however. So it clearly has some advantages. Also, if your greenhouse is going to use glass rather than PVC sheets, the wood construction needs to be thicker.
The best solution is typically a steel frame. While steel is going to rust over time, it will outlive most wooden constructions. It's also robust enough to hold even a large greenhouse with glass or plexiglass. Steel is also affordable. The main problem is it requires welding and tools for cutting steel. If you don't have these tools and skills, using it in a DIY project is out of question.
It's also possible to construct your greenhouse using plastic or PVC pipes. This is very common solution with hoop houses - the pipes can be easily bent and form the construction quickly. But you can use PVC pipes even for a gable roof greenhouse. They are robust, very easy to work with, and quite durable. Note only that plastic loses its durability from strong sunlight and low temperatures. So PVC pipes aren't the best solution for places with harsh weather.
At the end the choice of material comes down to your skills, tools, personal preferences, and financial calculations.
Heated or Cold
One major typization of greenhouses is whether they are heated or not heated (cold). Using artifical heat can greatly extend your growing season and give you fresh produce of even heat-loving vegetables during the winter. This comes with its price: not just the fuel for heating, but also installing proper heating appliances, watching out to keep the right temperature etc. In general the hobby greenhouses are usually not heated.
Any greenhouse that does not use artifical heat is considered "cold". This includes cold frames, sun rooms, hoop houses etc. You can consider using some kind of extra solar heating (via panels, mirrors etc) for a cold greenhouse and thus get better temperature inside. But sun is not available in the night which can expose your greens to greater temperature differences between night and day. To some extent this can be avoided by using thermal mass like buckets with water, stones etc.
By Purpose: Seed Starting or Growing
Most hobby homesteaders will use the same greenhouse for both although unheated ones aren't that good for seed starting. It might be best to keep your seedlings at home and bring them to the greenhouse only after they sprout. And make sure the night temperatures won't kill them!
Cold frames and small greenhouses will often be used only for seed starting because they are not high enough to keep high plants. Large greenhouses are typically using for extending the growing season and grow stuff like cucumbers and tomatoes earlier or later in the season.
A Bunch of Greenhouse Ideas
And if you need a bit of inspiration, we have collected a bunch of ideas for you:
- A straw bale cold frame which is quite cheap and does a good job with the insulation.
- Making a hoop house over a raised bed is a very typical and easy choice for the hobby garden.
- Since you are on a site moslty about sheds and barns, you'll love this one!
- A lovely fold-down lean-to greenhouse idea is available here.
- The geo-dome is a bit harder to make yourself, but it's very interesting and practical.
- Why not an underground greenhouse? They clearly have their advantages, although can often require more work and the sunlight during winter might be somewhat not sufficient.
- I also like this table-top greenhouse idea a lot. It's simple and good for seed starting or growing flowers and herbs.
Greenhouses are a huge topic and there are many sources of inspiration. It doesn't take much to start with a small cold frame and enjoy the benefits!