Here’s how to build cheap raised garden beds with cedar or concrete, as well as what to plant in them!
Every time I open a plant catalog or see a television commercial for sale-priced $99 raised garden bed kits, I cringe! You don’t need to spend that kind of money to build your own four-by-four-foot bed (or even a 20-foot-long one).
How to Build Cheap Raised Garden Beds
Building Raised Garden Beds with Cedar
My husband builds mine. He buys two 1x8-inch cedar boards, which don’t rot with age. They come in 8-foot lengths, which is perfect for 4x4-foot beds. Cut each plank in half, so that it is 4-feet long. Or, you can have a home improvement/lumber store make the cuts. Many places will do it for free.
My husband also buys a 3-foot length of a 1x1-inch pine stake; he cuts it into four pieces and uses them to nail the cedar boards at the corners for bracing. That’s all!
I place the boxes on cleared ground. We cut and roll up our turf, but many gardeners do not think it is necessary. The added 6 inches of soil will bury most of the grass and weeds beneath. After I situate the boxes (four or five grouped together makes a good sized garden), I put down three layers of newspaper to suppress errant weed or grass seeds that might sprout. Paper degrades fully within weeks and feeds the soil.
Building Raised Garden Beds with Concrete Cinder Blocks
Another fast, cheap method of building raised beds is to use concrete construction (cinder) blocks. They have a big bonus. Their holes can be filled with soil mix and planted with herbs or strawberries.
The extra gathered heat from concrete is perfect for Mediterranean-type herbs such as rosemary and lavender. Strawberry plants grow huge and fruit fast in the holes. Each block is 16 inches long by 8 inches high; I purchase mine at big box stores as find the price most reasonable. Beds of 13 feet or longer by 4 feet wide are cheaper to build using blocks than with cedar boards.
Get more tips on how to build raised garden beds
Planting in a Raised Garden Bed
Grouping together several raised beds makes a substantial vegetable garden that is easy to maintain, with no weeding and crops that mature fast.
You will be planting seeds and transplants close, because the beds are smaller and the soil is richer. But plants grown close together in raised beds mature faster, because they compete for nutrients and sunlight. Each plant senses the distance of others and adjusts its metabolism to compete. Several university studies have proven this competition syndrome by identifying how plants perceive others nearby using the green light spectrum.
This 4 x 4-foot bed is crowded with productive peppers, cucumbers, a tomato plant and insect-repelling flowers that are edible.
Get more tips for planting in raised garden beds.
Raised Garden Bed Soil Mix
The more organic matter there is in soil, the better. Soil microbes are fed, oxygen and water readily reach roots and plants thrive. Here’s the recipe I’ve developed in the last decade that works best for my garden.
For one 4 x 4-foot raised bed. (Multiply amounts to fill larger beds.)
- 4-cubic-feet of top soil
- 3-cubic-feet of coconut coir (Note: Traditionally, peat moss has been used as a component of garden soil, but given that it is not a sustainable material, we recommend using coconut coir instead.)
- 2 to 3-cubic feet of compost or composted manure
- 2-inch layer of shredded leaves or grass clippings.
If you use grass, make sure the clippings are not from a lawn that has been sprayed with herbicides or been fertilized with a food that contains granular herbicides to kill weeds. Both persist and will kill plants beds up to three years after the initial application.
Mix all materials with a hoe or cultivator and water well. Be sure to mulch well with organic matter such as more leaves or clippings or straw.
Watch our helpful video on building and planting in a raised garden bed! Plus, get more tips on building a raised vegetable garden.
Have you built your own raised garden beds, or do you have more questions on how to? Let us know below!