For me, greenhouses have always been a sign of a committed gardener. After all, they are supposed to get more growing time out of the year. However, greenhouses usually take up a lot of valuable garden space (and money!). But what if I tell you you can build greenhouses right on your raised beds? With a raised bed greenhouse, you get an extended growing season and happier harvests while saving space at the same time!
Raised bed greenhouses are a great DIY project, but they do require a little planning. You need to evaluate what your garden needs (think about location, materials, timing, etc.) before building. Then choose from one of the many designs that will work best for your particular raised beds. It all seems daunting at first, but we're going to cover everything you need to know!
Why a raised bed greenhouse?
A raised bed greenhouse reduces damage from bad weather. Source: alh1
Before we get into the technical details, let's make a raised bed greenhouse 101. Garden bed greenhouses differ from traditional greenhouses in that they are not temperature and humidity regulated. Instead of being artificially heated, these structures become warm the soil by capturing the warmth of sunlight. While the vegetables and flowers inside are a little more toasted, you can't really control the temperature or heat the soil enough to accommodate plants outside of your garden area. Another important difference is that raised bed greenhouses are smaller and often portable.
The slight difference in heat is useful at the beginning and at the end of the growing season, for example when winter sets in. Normally, your garden plants will feel the temperature drop and complete their life cycle (or go into the soil). . But if we raise the temperature and extend the growing season, we can get a few extra weeks or even months out of our garden. This works especially well with late harvest products like winter squash.
Along with harvesting later in the season, you can too plant earlier (which works in the garden most of the year!). It depends on the plants, but many can be planted in the ground for up to 1-2 months in the spring. Frost tolerant plants like spinach are excellent candidates for late winter planting in raised beds. To determine how early to start gardening, use a thermometer to observe how warm your garden greenhouse is getting and compare it to the planting temperature on the seed packet.
Raised bed greenhouses come in handy for spring and summer Protect plants from pests and adverse weather conditions. They are also great for gentle Hardening of new plants (or just babying your favorite herbs and vegetables!). In winter weather, when the ground is just too cold for gardening, a garden bed greenhouse helps protect the roots of temperature-sensitive, dormant plants in the raised beds.
Raised bed greenhouse vs. raised bed cover
Raised bed ceilings can serve as a temporary greenhouse. Source: Unconventional Emma
If you have raised beds, you have probably already looked into raised bed ceilings. Covers are fantastic for gardening, but they don't always take care of the raised bed and soil like a greenhouse. The crucial difference lies in the material. Raised bed covers are often made of fabric material with ventilation holes, mesh, or even chicken wire that will keep pests out but keep the heat out. Covers with a solid cover, like thick plastic or glass, are technically greenhouses because they keep the soil warm and viable. Basically, a raised bed greenhouse is a very efficient type of raised bed cover.
Things to consider
A greenhouse is a great addition to raised bed gardening, but it's not a panacea for your garden bed. It comes with some limitations and small obstacles that you should be aware of.
The biggest limitation is that a raised bed greenhouse won't grow every plant it wants. It will only help the soil reach a certain temperature and humidity, which completely depends on where you live. Plants that don't grow in soil or raised bed in your climate zone won't do much better in a raised bed greenhouse (sorry, but dragon fruit just won't grow outdoors in an Idaho winter). To do this, you need a greenhouse system with temperature and humidity controls.
Another important factor is that a raised bed greenhouse is absolutely solid, which doesn't allow for a lot of airflow. Even if it's not airtight, you need to get real airflow through the system to keep bacteria from growing. You'll also need to open the greenhouse during heat waves to make sure the soil temperature and roots don't get too hot (depending on the weather where you live).
After all, every greenhouse system creates a barrier between the pollinator and the plant. If you want to grow fruit, you need to open the raised bed greenhouse when the plants are in bloom.
Types of raised bed greenhouses
A large raised bed greenhouse can protect much larger plants. Source: Unconventional Emma
There are many variations in raised bed greenhouses, but most are one of two basic structures: hoop houses or cold frames. These categories have their pros and cons, but both are excellent choices for year-round gardening. There is also plenty of room for creativity!
We actually have a full article on raised bed tire houses, but here's a quick overview. Tire houses are usually the cheaper, temporary option. They have rounded frames (tires) that hold some sort of solid cover – usually a thick plastic. Tire houses are a quick DIY project that is easy to assemble and disassemble. For this reason, they are usually only set up when necessary. Because they are so temporary, tire houses rarely have hinges or easily accessible openings for ventilation.
Tire house structures should be made of something that can easily be bent into shape. Thin PVC pipe is the most popular choice because of its flexibility and ease of use. You can use thick wire, hoop house kits, or even hula hoops too! The cover must also be flexible, clear and durable.
There are several ways to mount tire houses on your raised beds. The easiest way is to just stick the ends of the hoops in the ground and then cover them. If you have wooden raised beds, you can nail the hoops directly to the outside of the bed. Or, for a more permanent solution, you can mount the hoop house in the raised beds before filling them with soil (as in the plan provided here).
Cold frame greenhouses are the fancier raised frame greenhouses that require some woodworking skills (or a fat wallet). They are attached to the raised beds, often on hinges, which makes them an integral part of the garden. Cold frames are used all year round and are slightly opened when necessary. Plus, they're usually the prettier option with a neat box design.
Cold frames typically have a wooden frame that is lined with high-quality plastic or glass. Many are just repurposed windows from house renovations. You can easily buy cold frames online or just create one of these 26 free cold frame plans!
Of course, you don't need to follow a pre-made greenhouse plan for raised beds. It's your garden so be free to get creative! You can combine ideas to create your own unique raised bed greenhouse. Or you can reuse something from a thrift store such as B. transparent storage containers or an empty aquarium.
Some gardeners will turn things around and build raised beds in a large, existing greenhouse. This is a fantastic option that will save a lot of space and make it easier to access the vegetables. Raised bed kits like the Birdies Raised Beds are the easiest to put together in a greenhouse, not to mention more uniform.
Build a quick, temporary greenhouse
Essentially, this temporary greenhouse is a shallow cold frame. Source: Rachel Garcia
Time is money (or vegetables in our case) so let's save some by quickly building a greenhouse that can easily be added to the raised beds. This raised bed greenhouse is a simple wooden box frame that can be made in a matter of hours. It's lightweight, so you can add and remove it from the raised beds if you need to.
This raised bed greenhouse design is laid flat over the top of the raised bed so it will only work with shorter or immature plants. However, you can easily increase it by adding legs or using thicker beams. For a sloping greenhouse where rain can run off the raised beds, use a thicker bar on one side and have the two vertical bars cut at angles.
Let's start by gathering some materials. Here's what you need:
- 5 wooden boards or posts (cedar, spruce or whatever is free in your garage)
- Greenhouse plastic of your choice
- Tape measure
- Wood glue
- Nails (or a related fastener)
- Metal brackets (optional)
Now just follow these steps to create your DIY raised bed greenhouse:
- Measure the length and width of your raised beds from the outside edges.
- Cut the wooden boards from these measurements to recreate the perimeter of the raised bed. Remember to plan in advance how you will be joining the boards. For example, if you are making a simple butt joint, the overlapping board will add a few inches more length to the second board.
- Cut the fifth board so that it fits over the center of the frame. If your raised bed is extra long, you may want to place two or more of these stabilizing boards over the frame.
- Use wood glue to put everything together. Also, drive nails through the ends for added durability. You can also attach metal brackets to the inside of each corner (cheap shelf brackets are great for this!)
- Set the greenhouse frame aside and grab your greenhouse plastic. Measure and cut enough material to line the entire frame.
- Use a staple gun to secure the greenhouse plastic to the frame. It should be taut, but not so tight that it will tear.
- All you have to do is test it! Simply place your new greenhouse frame on the raised bed and see how your plants react to it. You can change the frame as needed, e.g. B. increase or add hinges. For now, however, you have a good system for keeping the soil, plants, and roots in your raised beds warm.
Adapt your greenhouse frame to the needs of your garden. Source: Rachel Garcia
frequently asked Questions
Q: Can you put raised beds in a greenhouse?
A: Absolutely! Adding raised beds in your greenhouse will give you more space for gardening, improve drainage, and make it easier to access the plants than if they were on the ground.
Q: How deep should raised beds be in the greenhouse?
A: If you can only access the raised bed from one side, make it as deep as you can comfortably reach the ground (usually 2-3 feet). This also depends on the size of the vegetables, herbs, or flowers you are planting.
Q: Are raised beds warmer?
A: Yes, the floor gets warmer because it absorbs sunlight both from the sides and from above (floor near the floor only heats up from above). But that also means that the raised beds get colder just as quickly in winter – hence the greenhouse!
The green fingers behind this article: