What is a Raised Garden Bed?
Wood Framed Box
Built with wood
Most common Cedar or Pressure-Treated Pine
8 to 12 inches deep
4 feet wide, 3 feet if for children
Length usually 8 to 10 feet
For Cedar and Pine Bed Construction:
Construction Lag Screws
Hillman Groups 5/16-inch x 4 or 5-inch in length
Pre-drill both the end and side boards while they are set up
For beds 8-10 inches high, use 2 screws per corner (8 per bed)
The Hillman Construction Lag Screw uses a T30 star-bit driver, washers, galvanized 3/8 inch - 8 per bed
With 8-inch boards, put the screws are 1 1/2 inches from the top and bottom of the board. With 10-12 inch boards, put screws 2 inches from the top and bottom. You can also add a 3rd screw in the middle for 12 inch boards.
Mounded Rows
Mounded soil 8-12 inches high
2-4 feet wide
1-2 foot pathways
Length can be anywhere from 8-100 feet.
The Turner Farm Community Garden Program uses 30-inch beds with 18 pathways.
Solarizing to Develop New Beds on a Grass Field
Solarize grass using translucent or black plastic sheeting, for four to six weeks, during July and August is best. Plastic should be at least 4 mil in weight.
Installation: Dig a shallow trench 4 inches wide and 3-4 inches deep (or an inch or so below the grass roots) around the area to be solarized - when placing the plastic run it to the edge of the trench. Secure the plastic with weights (i.e. bricks, logs, boards…) or garden staples.
Tilling:
Deep tilling can be helpful prior to solarizing to break up compacted heavy soil and expose grass and weed roots to direct sunlight.
Shallow tilling can be beneficial after the plastic has been removed to prepare compacted soil for sowing cover and green manure crops. After solarizing do not deep till because it may expose weed seed.
Follow with a cover crop of Walnut Creek Fall Cover Mix, see page 3 for information on mix composition. If it is too early for a fall cover crop sow Buckwheat, then follow with a fall cover crop.
First-year planting recommendations: Legumes, Potatoes, Sweet Potatoes, and for the fall Winter Squash.
Building a Sheet Compost Bed
Sheet Compost Bed, a variation on a Hugelkultur bed, using existing compost pile debris and/or partially decomposed woodchips (with hoed weeds) from garden pathways. Recommended time late spring/early summer or the fall.
Mark the perimeter of the new garden bed, then dig a trench approximately 4 - 5 inches wide (width of hoe or Maddox) and 4 inches deep (just below the grass root zone). This is to create a buffer to discourage the grass from traveling into the new bed.
Spread out an even layer of coarse material from the compost pile.
Continue with a layer of smaller material, then successive layers of finer material from the compost pile until the bed is 8 to 12 inches deep.
Top bed with finished compost or composted manure. (Optional)
Sow the bed with a Buckwheat cover crop, then cover with a light covering of straw.
When the Buckwheat flowers cut it back at ground level then follow with succession plantings as needed.
In August, cut back the Buckwheat (do not turn) and plant a crop of squash and or bush beans for a fall harvest. Another option would be Hairy Vetch, cut back once flowering - chopped and dropped do not turn in.
In the spring plant a crop of potatoes and/or sweet potatoes, mulch them as needed with straw or leaf mold. Harvesting the potatoes will be the first time you will dig into the bed and will give you an idea of the status of the soil. Your next crop should be determined by the condition of the soil.
Straw Flake Garden Bed
The community garden is a variation of the Turner Farm Community Supported Agriculture model offering participants the opportunity to work in a community-based garden, share the harvest, learn gardening skills, and the option to earn a raised garden bed for their home by participating in the Learn-Grow-Earn program.
This method uses "flakes" of straw over a new or existing garden bed as a form of sheet mulching to smother weeds, retain moisture and to build healthy biologically active soil.
Bales of straw are broken into flakes approximately 2-3 inches thick and laid flat on the soil surface in a grid. The row or bed can be between one to four sections wide.
After laying out the straw flakes bedding plants are planted or seeds sown into the soil between the flakes, or holes can be cut in the flakes and plants or seeds inserted through the straw into the soil. Compost can also be added to each hole.
Please note that when direct sowing seeds, larger vegetable plant varieties such as beans, summer squash, and okra are best suited for this type of garden.
§ Broad Fork for aerating soil.
Composting
If the compost system is maintained over successive years, the windrows will decompose more completely and at a faster rate. Turning the windrow two or three times a year will also facilitate the process. In addition, adding horse or cow manure will facilitate decomposition and improve the nutrient content of the compost.
Do not allow weeds to go to seed and do not put weeds that have gone to seed into the compost windrows.
Create and maintain a small compost windrow or pile in your own garden plot. An advantage of this technique is the gardener can be sure weeds that have gone to seed and diseased plants are not in the compost. The compost can be part of their garden crop rotation plan and can be planted with a vining crop so the space will have a layered (double) use.
Compost Windrows
In late fall, after garden beds have been cleared for winter, turn or re-layer windrows and allow them to overwinter.
If horse and/or cow manure is available turn it into the compost windrows.
New Garden Beds
Allow sheet-composed beds to mature for 6 months with a cover crop of buckwheat.
The buckwheat can be followed with a fall crop of winter squash or bush beans.
Cover beds with straw or leaves during fall and winter.
Tools
For maintaining a pathway, a long handle Stirrup Hoe and/or Low Wheel Cultivator with a Stirrup Hoe or Sweeps/slicing blade attachment is recommended.
Narrow Collinear Hoe Fixed Blade and Collinear Hoe with Replaceable Blade (Johnny’s Select Seeds)
Broad Fork for aerating soil.
Suppliers
Cover Crop Seed
Walnut Creek Seed
www.walnutcreekseeds.com
Fedco Seed
www.fedcoseeds.com
High Mowing Seeds
https://www.highmowingseeds.com/
Tools Low Wheel Cultivator (Wheel Hoe)
Earth Tools
earthtoolsbcs.com
* Also sells Broad Forks
Hoss Tools
www.hosstools.com
Planet Jr.
www.planetjr.net
Books
Jean-Martin Fortier
The Market Gardener
New Society Publishers, 2014
Toby Hemenway
Gaia's Garden
Chelsea Green Publishing, 2001
Amy Stross
The Suburban Micro-Farm
Twisted Creek Press, 2017
www.tenthacrefarm.com