Raise your garden game: Tips and tricks on raised beds from UW Garden Expo

Memorial Day is the rule of thumb for last frost in Wyoming, and gardeners may be looking to try out a trend – the raised garden bed. 

Erica Reasoner, Crook County 4-H Educator, gave a talk on raised beds at the UW Extension Garden Expo in Basin last month, sharing tips and tricks on how to make your raised beds most bountiful. 

“There’s something like a science with this,” Reasoner said. 

The benefit of a raised bed versus in-ground planting largely comes down to control, Reasoner explained. By lifting garden beds, gardeners have the capacity to mix their own soil rather than amending any existing mineral or nutrient problems. 

“Don’t buy potting soil for raised beds,” Reasoner said. “Buy soil specifically mixed for raised beds or build your own.”

Reasoner recommended a mix of 60% topsoil, 30% compost and 10% organic material, such as coconut coir, peat moss or vermiculite. To avoid purchasing an entire bed’s worth of soil mix-ins, gardeners may use cardboard, leaves and wood to partially fill the bottom of their beds. Leave room for about 10 inches of dirt on top. The filler will break down over time to feed the plants and save a buck. 

Grass clippings can be used to fill in raised beds or as mulch, but Reasoner suggested avoiding this method if your lawn is treated with herbicides or fertilizers that may affect plants in the bed. 

Raised beds are also ergonomic; there is less kneeling and bending than traditional gardening.  Reasoner suggested building beds long and narrow ­— 4-foot by 8-foot and 12 to 24 inches high — so that they can easily be reached across. This makes it easier to plant, water and weed. 

To prevent weeds from popping out the side of raised beds, gardeners may want to purchase weed fabric for lining. This will limit the number of weeds while allowing moisture to pass through, unlike plastic liners. Some conservation districts sell the fabric in 100-foot rolls. 

As far as building the bed itself, there are a few options. Untreated wood, metal and cinderblocks are common choices. Metal and some woods may help retain heat in the soil, extending the growing season, but also potentially drying out soil. Reasoner recommended cedar, which is a natural pest repellent. 

Pay attention to the level of sun or shade in the area you choose to build your planter, as well as how level the ground is. This will help with watering. 

Reasoner has water lines installed on her planters, which allows her to set a timer and forget about it. Drip line, as well as mapping suggestion pamphlets, can be found at Ace Hardware. 

PVC pipe can be used to build a frame for shade or insulating plastic to help control the plant environment as well. 

Cooler plants, like lettuce, peas and spinach can already be in the ground safely. Warmer plants, like tomatoes, peppers and squash, may need started inside or monitored carefully before threat of frost subsides. 

When picking plants, don’t overcrowd and consider companion planting to avoid competition. 

“Gardens don’t have to be planted in rows,” Reasoner explained. 

Tomatoes, for example, grow well with basil, marigolds, carrots and onions. Research what plants will grow well together, then remember to rotate crops next season so the same plants aren’t sucking up the same nutrients. 

For more gardening and agriculture information, visit https://wyoextension.org/bighorncounty/ or stop by the local UW Extension office at 208 S. Fifth St. in Basin.