Budget-Friendly DIY Raised Garden Greenhouses

I live in a Plant Hardiness Zone 3 which doesn't give us a long growing season. To make matters worse our yard faces north and we live in a mature neighborhood with a lot of trees which = shade. Achieving a high yielding crop of veggies has been a challenge when some years we still have snow on the ground in April and May.

Starting plants indoors is also not an option when you live in a small home so we took matters into our own hands to extend our growing season by building budget-friendly mini greenhouses for raised garden beds.

DIY Raised Garden Greenhouses


Budget-Friendly DIY Raised Garden Greenhouses 


Small Raised Garden Greenhouses
Our inspiration came from Stephanie at Swing N Cocoa who came up with a brilliant design.


Last weekend we took advantage of it being a long weekend and got to work building one for each of our three raised garden beds.  We modified ours somewhat from the original design but more on that further down in this post.

Materials List

(for each greenhouse based on 4' x 6' beds)
  • 3 each 2 x 2 x 8 lumber
  • 5 each 10' PVC pipe 
  • 8 pipe clamps
  • wire mesh
  • 2 hinges
  • 1 handle
  • 4 each 3-sided metal corner brackets
  • galvanized screws
  • light chain
  • 6 mil roll of poly

Building the greenhouse base

Cut the 2 x 2's at 45° angles the same length as your raised gardens.  Drill a pilot hole into each joint to avoid splitting when screwing them together.

Mini Greenhouses for raised garden beds 2 x 2 frame

Apply carpenters glue onto the joint and drill a screw into each pilot hole to secure the joints.

Mini greenhouses for raised beds 2 x 2 frame

Install 3-sided corner brackets for extra support (sorry we forgot to take close up pictures). This is important considering the greenhouses will frequently be lifted up an down.

Mini Greenhouses for raised beds frames

Building the PVC greenhouse frame

Secure pipe clamps along the inside of the frame on each side to support the PVC pipe. Ensure the distance between each pipe is measured equally. We purchased 1/2-inch PVC pipe in 10-foot pieces and cut them down to 8-feet.

Note: Don't throw out the 2-inch off cuts because you'll be using them later.

Mini Greenhouses for Raised Beds pipe clamps

Insert the PVC pipe into the clamps and tighten the screws to secure in place.

Mini Greenhouse for Raised Beds PVC Frane

Find the center point of the greenhouse as pictured below...

Mini greenhouses for small beds PVC supports

The salvaged 2-foot cut offs of PVC pipe you saved are used for the center supports.

Mini Greenhouses for raised beds securing frame with electrical tape

Secure the 2' pieces of PVC pipe along the center of the top using white electrical tape. This will stop the pipe from moving around and add support for the poly.  Another more costly option for joining the pipe is using PVC tee fittings and couplings.

Mini Greenhouses for raised beds top supports

In the original design, you would secure wire mesh over top the PVC which we purchased but got so frustrated, let alone sustained a few flesh wounds and decided to come up with Plan B.

IMPORTANT UPDATE:

It didn't take long for us to learn WHY the need for wire mesh. Rainwater tends to pool on the top, putting a lot of pressure on the poly and so don't do what we did and avoid this step, it's an important one. You only need to install it along the curved portion.

To add more stability to the sides we attached more strips of 2-foot PVC pipe just where the sides start to curve. Take a measurement from the base so they all line up perfectly.

Mini greenhouses for small beds side supports

Covering the greenhouse frame with poly

Cut the poly large enough that it covers the front of the greenhouses s as well. Starting on the sides attach the poly to the bottom of the 2 x 2 base with staples, starting in the center. Move to the opposite side and pull the poly tight enough that it removes any dimples in the plastic but not so tight that it distorts the shape of the PVC.

Mini greenhouses for raised beds with poly

Now you can deal with the front of the greenhouses in a couple of ways.

Option A:

Start in the center and fold the plastic to form pleats and staple in place along the bottom of the base. We tried this technique but didn't like the look.

Option B: 

Our preferred option. Pull the poly taut and starting in the center staple it onto the base. With a nurses fold - think about how Grandma taught you how to make a bed - fold the fabric taut to the sides and staple it onto the base. With a retractable knife remove the excess plastic along the bottom of the base.

ANOTHER IMPORTANT UPDATE:

Debris accumulates in the folds so to avoid this from happening you have two options:
  1. Place the fold on the INSIDE of the greenhouse
  2. Add clear tape along the fold (not as aesthetically pleasing)

Installing the greenhouses onto the raised beds

Set the greenhouse on top of the raised bed and secure it on the back with two hinges. We placed our hinges 1-inch toward the center on each side. 

To keep the greenhouse from flying backward when you open it or from a strong wind catching it, attach some light chain on each side as pictured below. 

Mini greenhouses for raised beds with hinged top

Attach a handle to the center of the base for easy lifting.

Mini greenhouses for raised beds with handle and hinges

And there you have it, DIY raised garden greenhouses. They might not be as pretty as the mini greenhouses you see made from salvaged pane glass doors but they're a great budget-friendly option.

You can see in the photo below that I temporarily stuck some 2 x 2's into the soil and have them resting on the greenhouse bases for ventilation on hot days. I plan on coming up with a better system when time permits. I'm toying around with the idea of mounting the 2 x 2's onto the front of the raised beds with washers so they swing up when you need them or down when you don't.

Mini greenhouses with raised beds tilted tops for ventilation

You can see the nurses fold better in the photo below. 

Mini greenhouses for raised beds

The frames will not withstand the weight of snow during the winter months so the greenhouses will have to be removed and stored. It's an inconvenience we are willing to make if it means yielding a better veggie group in our cold climate.

Mini greenhouses for raised beds

The frame laying on the grass in the forefront of the photo above was removed from our deck (another project in the works) but more about that another time.


So are they working?
I planted these tomatoes the first week of June (three weeks ago) from 4-inch pots and already the plants have almost doubled in size with a lot of tomato growth and flowers - without the use of fertilizers.

If you found our budget-friendly DIY Raised Garden Greenhouses inspiring, please share them with a friend and/or save on Pinterest.
Budget-Friendly DIY Raised Garden Greenhouses
Here are some other DIY Outdoor Projects we made for our backyard that you may find inspiring.
Repurposed Louvered Bi-fold Door Privacy Screen
Plant Pot Water Fountain
DIY Outdoor Water Wall
Solar Flower Pot Water Fountain
DIY Patio Expansion


I share my projects here at these fabulous link parties.




Show Comments: OR