Gardening: Raised beds: Thinking inside the box
Mar./Apr. 2009 California Country magazine
By Pat Rubin
Raised beds in the garden allow the soil to dry out and warm up faster in spring so you can plant earlier.
Years ago my vegetable garden was a spacious 60-by-20-foot plot. Come spring, we’d spend days pulling weeds and tilling. It was tedious, time consuming and dirty.
Today the garden is a series of raised beds with bark-strewn paths. Why?
The soil in raised beds dries out and warms up faster in spring so you can plant earlier. You’re not walking on the soil, so it doesn’t compact; you can plant more densely; and you’re bringing in fertile soil rather than digging down into poor soil. You can easily build a raised bed yourself, or order complete kits that literally snap together.
Location: Pick a level, sunny spot with a water source nearby. Remove weeds and grass. Rough up the soil a couple inches deep.
Materials: Anything goes for edging the bed. My choice is 2-by-12-inch redwood. That gives you plenty of soil depth as well as enough room to sit on the edge of the bed to work.
Size: A raised bed can be any length you like, but shouldn’t be any wider than 4 feet so you can reach into the middle.
Construction: If you’re not handy with a saw, have the lumber store cut the wood. Nail or screw the sides together, then use brackets or metal straps to keep the boards firmly in place. We use deck brackets that fit a 2-inch-wide board. If you have gopher problems, line the bottom with 1/4-inch mesh hardware cloth. Next, install a drip system.
Soil: Fill the bed with soil that smells sweet and has a nice texture. Mix together, tamp down.
Planting: Plant in clumps or groupings, not rows.
Pat Rubin is a long-time gardener and garden writer. Send questions or comments to her at email@example.com.
Choosing the best soil for your raised beds
Visit the nursery or garden store and ask about their bulk vegetable garden soil mixes. Most have mixes that contain topsoil as well as compost. A tip: Do not buy potting soil designed for indoor plants.
Buying in bulk is cheaper than buying bags and you can see what you're getting. For example, a cubic yard of soil costs about $30. To purchase the same amount of soil in bags would cost about $70. (A 2-cubic-foot bag of soil costs about $5, and you'd need seven bags to almost fill a 1-by-4-by-4-foot raised bed.) If you have to buy bags of soil, it's not the end of the world. There are plenty of companies that produce fertile, nutrient-rich bagged soil.
Scott Meyer, editor of Organic Gardening, says, "Take the sniff test. If there's anything that smells sour or off or acidy, that means it's not fully decomposed. Look for soil that smells sweet and earthy and has a nice texture. Squeeze it together, and it should clump, but not form a hard clay ball. It shouldn't just sift through your fingers."
The best soil, Meyer says, is mushroom compost. "It's really fertile and it's been inoculated with fungi, and that's really desirable. You want fungi in the soil because it helps hold soil together. It's biologically active."
Fred "Farmer Fred" Hoffman (www.farmerfred.com) carries an inexpensive pH test kit when he goes to buy bulk soil.
"I test the pH. If it falls within the parameters of 6.0 and 7.5, that's what I'll get since most vegetables grow well within that range." Be sure to get soil from the load that you test, Hoffman says, since the next shipment might be different.
To determine how much soil you need, multiply the height times the width times the length. Our 1-by-4-by-4-foot bed (1-by-4-by-4) can hold 16 cubic feet. A cubic yard (3-by-3-by-3) is 27 cubic feet, so a half-yard combined with compost will fill the bed. Fill it completely to the top and save some soil in reserve because it will settle a bit.
Add soil and compost alternately, and then mix them together using a shovel or a rake or a small tiller. Tamp the soil down with the back of the rake or with a piece of wood before planting. Finally, we put chipped bark on the paths around the bed for a tidy look and to keep soil from splashing against the wood.
Thinking about drip irrigation?
Installing a drip system is no more difficult than putting together a puzzle, and it can actually be fun. Take a look at what the local nursery or plumbing store has to offer and ask one of the employees to explain the pros and cons of the various systems.
I use one called o-jets. It's been around for 20-plus years, and I simply replace or reconfigure parts of the system as needed. I can easily add emitters or take them away. I can snake the lines through plants and move them during the season as plants get bigger.
But what I like best about it is I can get emitters that spray various angles (90 degrees, 180 degrees) and that spray various amounts of water on the same system. I can have emitters that put out plenty of water for thirsty plants as well as ones that are far stingier with the water. I prefer the spray system to a straight drip because I like my irrigation system to put some water in the air around the plants and to hit their leaves.
Gardening to-do list for March/April
- Resist the temptation to plant beans, corn and squash in the ground until soil temperatures reach 50 to 55 degrees. Otherwise, the seeds will simply rot in the ground. And remember not to till or dig when the ground is wet since this causes soil compaction.
- Seeds to plant in the ground now include beets, radishes and carrots.
- Prune grapes, trim frost-damaged perennials and begin feeding citrus trees.
- For a larger, higher-quality crop, thin fruit on trees when young fruits are 3/4 to 1 inch in diameter. Space the fruit 6 inches apart.
- Resume feeding houseplants.
- Wash aphids off plants with a strong spray of water, or use insecticidal soap. Insecticidal soap only works when you spray it on the aphids; it doesn’t prevent aphids. If you see ants on the plants, chances are the ants are “milking” the aphids for the honeydew. Use sticky tape or a product like Tanglefoot to keep ants away.
- Hang yellow jacket traps now to catch newly emerged queens.
- Feed camellias, azaleas, gardenias and rhododendrons with an acid-type fertilizer. If the leaves are yellow, use a foliar spray containing iron and zinc.
- Cut back spring-blooming bulbs after the foliage has turned brown.