Have you ever wondered how to extend the growing season in a low cost, easy way? Building a DIY raised bed hoop house is the answer. This guide provides a step by step approach to building your very own hoop house. Follow our guide and video to build your own protected growing space to start crops in the very early spring before the last frosts.
Step 1: Items needed to build a hoop house
The following items are what we used for our DIY raised bed hoop houses:
2×2 timber for the base frame. This should be the length and width of the raised bed ideally in 4 lengths only, i.e. if possible use a single length of wood for the sides
2×1 timber for the sandwich frame to hold the polytunnel cover in place. As with the 2 x 2, ideally 4 lengths as long as each of the sides and ends
20mm diameter blue PVC pipe, we used 5 lengths of pipe. Our width is 90cm and height is 75cm, meaning each length is approximately 150cm.
75 micron/300 gauge transparent plastic polytunnel cover. Ensure that this is wide enough to cover the height of the hoop house, not just its width.
2 hinges
Various screws
A raised bed.
A hoop house could be built directly on the garden beds if you do not use raised beds. There would be no need for the hinges then.
Step 2: Make a frame
We made a timber frame to fit the size of our raised beds. Using 2 x 2 timbers for the frame made it strong, but light enough to lift up and down.
The timber frame was screwed together at the corners with metal right angles.
Next step was to fix the frame to the raised bed using the hinges. It is easier to do this now whilst the frame is flat, and before you add the third dimension, otherwise it becomes very unwieldy to attach. Fix the hinge to the frame first and then fix the other side of the hinge to the raised bed.
The final part of the frame is to create an upright at each end and a cross member down the middle. We did this using 2 x 1 again for lightness. The cross member is there simply to provide something to fix the PVC pipe to.
Step 3: Secure the hoops
We cut 5 hoops to the same length using a handsaw. Hoops are spaced at approximately 80cm apart.
Hoops are secured by drilling an ordinary self tapping timber screw through the plastic pipe. We tried to pre-drill, but the easiest way was simply to hold the pipe in place and drill straight through the pipe and into the wood below. We also added a metal lug at the corners for added security.
Step 4: Install the plastic
With the hoops in place we were able to secure the plastic.
We did this with a length of 2 x 1 timber on top of the base frame. This makes a timber sandwich that secures the polytunnel plastic in between and holds it firmly in place. It is useful to have 2 people to do this job, one to pull the plastic tight and the second to fix the timbers in place.
Step 5: Grow your veggies in a protected nursery space
As soon as the plastic is in place the effect is instantaneous. The wind is kept out and the sun’s rays are trapped making a warm space. Planting can happen immediately. Seeds can be planted, seedlings transplanted.
Take the time to observe how much quicker things grow within the hoop house compared to planting the same outside. We have harvested radish leaves within 4 weeks from our hoop house compared to 6 weeks outside.
Is a hoop house as good as a greenhouse?
A hoop house and greenhouse do two different but similar jobs. They can be used interchangeably in some cases. But they are best used for their specific design.
A hoop house is excellent for raising seedlings. It provides a warm, frost free and wind free environment throughout the spring. A hoop house is usually built on top of a raised bed which means that the seedlings can grow in situ into plants. The polytunnel element can remain in situ throughout the summer, or be removed depending on what is growing.
Some plants will grow too big for the polytunnel of a hoop house meaning that either the plant or the cover will need to be moved. It is important to think about this when planning your planting. For example tomatoes could be started in a hoop house but they will outgrow the height. Carrots, beets and leeks could all be grown in a hoop house for earlier crops than could be achieved planting outside. Whilst these crops can be transplanted from a greenhouse to a final growing location, allowing them to grow entirely in one place is great for producing abundant crops.
A greenhouse is also excellent for raising seedlings and for growing warm loving plants. Greenhouses have more height than hoop houses, meaning that they lend themselves well to raising seedlings that will be transplanted later. They are also good for growing taller plants such as tomatoes, or plants that can grow up, on a vine such as cucumbers or melons.
Interestingly you could always use the hoop house like a cold frame, and raise seedlings in seed trays under the hoops if you were not ready to plant permanent crops in the space. Or even in between rows as the seedlings are becoming established. Once the heat is trapped, make use of it!
And here it is our DIY raised bed hoop house in action:
FAQ
What do I need to build a hoop house?
To build a hoop house on a raised bed you need timber, PVC pipe and polytunnel plastic.
How do you secure a hoop house to the ground?
We secured our hoop house to a raised bed using hinges.
If you were not using a raised bed, a timber frame hoop house could be made as per the instructions above. This could be secured to the ground using ground stakes or rebar installed through pre-drilled holes in the timber frame. Or heavy rocks could be used to hold it in place.
How effective are hoop houses?
Hoop houses are very effective for raising young plants at the start of the season. You can plant a few weeks earlier into hoop houses as the plants will be protected from frost and cold winds. Seedlings will grow more quickly in a hoop house than outside due to having additional heat trapped within the hoop house. Overall they are effective.
Can you use PVC pipe for a hoop house?
Yes PVC pipe is great to use for a hoop house because it is flexible and strong. We use a 20mm diameter pipe.
How do you keep a hoop house warm?
A hoop house stays warm because the sun’s energy gets trapped inside the polytunnel. It stays warm on its own and does not require additional warming. Of course as the sun disappears at night the temperature will drop. For this reason a hoop house is great for use through the shoulder seasons. It may not be the solution for growing throughout the winter.
How thick should hoop house plastic be?
We used 75 micron/300 gauge transparent plastic polytunnel cover
What is the spacing for hoops in a hoophouse?
We used approximately 80cm spacing. However that was based on dividing our total raised bed length into 5 equal spacings. It might be better to consider whether to divide into 3, 4 or 5 hoops depending on the length of your raised bed.
How do you put plastic on a hoop house?
For us the easiest way was to use timber to make a sandwich with the plastic held securely inside two pieces of wood. This eliminated the risk of piercing the plastic when fixing it in place. As well as providing rigidity to the frame structure.
How do you bend PVC into a hoop?
PVC pipe has a natural curve from being stored rolled. Making use of this and following the natural curve, rather than working against the grain, allows the pipe to bend into the hoop shape required for a hoop house.
Conclusion
Follow our step by step guide to create your own protected, sheltered space to raise young plants. It is simple to build and very effective at growing seedlings. This hoop house is especially good if you don’t have space for a polytunnel or greenhouse, but you still want the benefit of protected space to raise seedlings.
I would love to hear how you got on in the comments below.