Raised bed checklist
raised bed
February 28, 2014
  • /ACES
  • /ACES News
  • /Crop Sciences

URBANA, Ill.- The idea of putting in a raised-bed vegetable garden can be confusing if you’re not sure where to start, said a University of Illinois horticulture educator.

It can be especially difficult for schools and communities that have never put in gardens before. Spring is a great time to start planning for this year’s garden, said Candice Miller.

“A checklist can be helpful in putting in a raised-bed garden,” Miller said. “The list below can help you work through all the steps of putting in a raised-bed garden, from selecting a location for your raised bed, all the way through planting your bed.”

Step 1: Choose a location

  • The location for a raised bed should be in full sun for most fruits and vegetables.
  • It should be near a water source for easy watering and should be close to the building for convenient harvesting.
  • The bed can face any direction, but if you are building a longer bed, orienting the bed east and west will provide better light distribution.

Step 2: Kill off existing vegetation where your raised bed will go

  • Grass and weeds can grow up through the new bed so it’s best to kill off any existing grass and weeds prior to putting the soil in the bed.
  • This can be done naturally by placing plastic, cardboard, or layers of newspaper down over the vegetation. This will eliminate all light from the plants and will kill off the growth over a few months’ time. This can be done in the fall so that the area is ready for spring planting. Newspaper or cardboard can be left at the bottom of the bed as it will degrade, but plastic should be removed prior to placing soil in order to not impede the drainage of your bed.
  • Another method is to spray the existing vegetation with a herbicide, like glyphosate, to kill all existing vegetation. Follow the safety and application instructions on the product label.

Step 3: Choose your construction materials

  • Raised beds can be constructed out of just about anything. Some of the most popular choices include redwood or cedar wood, concrete blocks, bricks, stone, and various recycled materials.
  • Redwood and cedar are some of the longest-lasting woods for building raised beds.
  • Some materials you want to avoid include some treated lumbers (read more about treated lumbers here: http://pubs.cas.psu.edu/freepubs/pdfs/uc173.pdf), creosote-treated railroad ties, and chemically treated pallet wood. Avoid any type of material that may be dangerous for food products to come in contact with. If these materials are used for bed construction, the bed may be lined with plastic to avoid contact of the materials with the soil.
  • Choose whatever material will be the most economical and long lasting for your bed.

Step 4: Build your bed

  • The size of the bed will depend on the number of people the bed will provide with food.
  • Beds should be no more than 4 feet wide if accessible from both sides and 3 feet if accessible from one side. The length of the bed can be as long as needed.
  • The depth of the bed should be at least 6 to 12 inches to promote good root growth.
  • Beds built higher than 18 to 24 inches will need extra reinforcement.
  • At least a 4-foot-wide pathway between beds is standard for easy accessibility. This pathway can also be covered with mulch, straw, newspaper, etc., to prevent weeds. It can be planted with grass as long as the pathway is large enough to allow a mower to pass through.

Step 5: Fill your bed with soil

  • The soil used for the bed should include good topsoil and lots of organic matter. This can be any combination of: purchased topsoil, compost, fine pine bark mulch, or peat moss.
  • A soil mixture example could be: 60 percent topsoil, 30 percent compost, 10 percent soilless growing mix that contains peat moss, perlite, and/or vermiculite.
  • Various websites have soil calculators available that can tell you how much soil is needed for a certain bed size.
  • It’s recommended (though not required) to test the soil using a soil test kit prior to planting and in years following to monitor pH and nutrient levels.

Step 6: Plant your bed

  • Nearly anything can be grown in a raised bed. Cucurbit crops like melons and cucumbers may be better suited to a larger site though as they quickly fill a bed.
  • Plant spacing is very important in a raised bed so that prime planting space is not wasted. Consult your seed packet for information on proper spacing. Information can also be found on U of I Extension websites (http://web.extension.illinois.edu/vegguide/step02.cfm) and in various books about ways to maximize planting space.
  • Be sure to place taller vegetables on the appropriate side of the bed to prevent shading of other plants in the bed.

Visit the Illinois Vegetable Garden Guide website by U of I Extension for more information on raised beds and vegetable gardening: http://web.extension.illinois.edu/vegguide/.