Raised Bed Master Gardeners

Raised beds dry out faster than traditional gardens, especially in the summer heat of the Yakima Valley.

Two weeks ago in this column, we shared information about raised bed gardening.

If you’ve decided to take the plunge after looking at all the advantages — and the few disadvantages — it’s time to take the next step. This week, we’ll discuss how to get started using the “contained” method.

Planning is half the fun. Once you’ve chosen a suitable location for your raised bed(s), sketch out your vision for your new garden. It’s best to make decisions before going to too much trouble and expense. Decide on the size, shape and materials you plan to use to contain the beds. Once the beds are built (or purchased) and put in place, decide on materials for the paths. This can all be done this fall, or it is OK to wait until next spring.

The next step will be filling the beds with soil. Evaluate your property’s soil for depth, texture and compaction to decide whether you can fill your new beds with native soil.

Texture tells us about the ability of soil to hold and drain water and hold nutrients. Soils that are a mixture of sand, silt and clay (called loams) are generally the best soil. You can always go to the local WSU Extension office and ask about having a soil test performed.

Well-aged animal manure and compost are wonderful additives to good native soil. Chemical fertilizers with a balance of 10-10-10 can also be added. High fertility allows for intensive gardening practices such as intercropping, succession planting and extended season crops.

The other important planning consideration is watering your beds. Keep in mind that raised beds dry out faster than a traditional garden, especially in the summer heat.

Approach watering with the idea that it’s better to work smarter, not harder. Think about adding drip irrigation. Drip irrigation uses less water than conventional methods; it is easily installed by the home gardener; and it can be easily customized to your garden. In addition, the water is applied at a slow rate at the root zone so is more easily absorbed by plant roots, and lessens the chance of disease problems caused by wet foliage. The best part is that it reduces weed growth.

Start from your water source and lay out 1/2” poly tubing along the path (you can even hide it under the pathway) to the bed(s). Then place a T in the tubing that goes directly into the bed. Depending on the size and shape of the bed, you can use large tubing with emitters you space or purchase tubing with internal emitters evenly spaced. Connections for poly tubing include: straight (used when extra length is needed or if you accidentally cut a line); T connectors (used to connect several lines or to change direction) and L connectors (used to change direction or to end the last line). Another choice is to use the small spaghetti or micro- tubing. You can also have shut-off valves at each bed or within the bed. That’s handy when you no longer need to water in a particular row.

The only minor disadvantage to drip irrigation is you may need to water more frequently at lighter rates, However, other than turning it on and off, there is very little maintenance.

Now that you have soil and water, you are ready to plant your bed in the spring. You can plant certain vegetables (such as beets, carrots, lettuce, chard, etc.) in rows, but make sure you adhere to the exact spacing requirements for each plant.

A better alternative with bedding plants such as cauliflower, broccoli, cabbage, etc., is to alternate the plants. In order to do this you need to know the diameter of the mature plant as you want them to touch but not overlap. The advantage of that is to reduce sunlight on the soil, thus discouraging weeds.

Another way to discourage weeds is to mulch between plants when they are growing — grass clippings work great. Sprawling plants such as cucumbers or squash, can easily be trellised with a stake, wire cage or small fence. Get creative and repurpose an old metal headboard. Vertical gardening again maximizes the amount of produce you can grow in a small space.

Always plant pollinators within your beds, not only for their beauty but to attract the bees necessary for pollination of many of your plants.

We hope you will find this new way of gardening in raised beds a great way to have more free time to enjoy the beauty around you.

WSU Extension Master Gardener Program is an organization of trained volunteers dedicated to horticulture and community service. The Master Gardener Walk-In Diagnostic Clinic operates from 9 a.m. to noon and 1-4 p.m. Mondays, Wednesdays and Fridays. Direct questions about gardening, landscaping or this program to the Master Gardener Clinic at 509-574-1604, or leave samples for identification at the WSU Extension office. Leave a message with your name, phone number, email address and the nature of your problem or question. You can also email your questions to gardener@co.yakima.wa.us and include pictures if you have them. A member of the Master Gardener Clinic team will check voicemails and emails, and reply as soon as possible. The WSU Extension office is at 2403 S. 18th St., Suite 100, in Union Gap. Call 509-574-1600. New volunteers are welcome.