Rise and shine, everybody. It’s time to get out of your bed and jump into a raised garden bed.
For beginners and gardening veterans alike, raised garden beds are ideal for growing flowers and vegetables.
They differ from garden planters. Planters are elevated (standing waist high) containers which have bottoms to prevent the soil from falling out. A raised bed sits on the ground. It does not have a bottom, which allows plant roots to reach additional nutrients deeper in the soil.
Raised beds can be as simple as forming a mound of soil without the use of any type of box. This brings us to the word of the day … hügelkultur. It’s a German word that’s pronounced “hügelkultur.” (I really don’t know how to pronounce it so I will substitute it with the words “big pile of dirt.”). It’s basically a small hill made from decaying wood, branches and plants, as well as compost and soil.
Raised gardens are easier to maintain than those in-ground. They also add to a yard’s visual appeal and can be square, rectangular, tiered or u-shaped. Let your creative juices flow. Earn accolades. Win prizes. Or none of the above.
Materials used for raised beds include untreated wood, pressure-treated wood, concrete/cinder blocks, and boards made with recycled plastic.
Untreated wood is fairly inexpensive, but it begins to decay within three or four years, if not sooner, even if you use rot-resistant cedar or redwood.
It’s not safe to use lumber treated with the wood preservative chromated copper arsenate (CCA). In plain English, that means arsenic. You’d recognize it by the timber’s greenish tint. My investigative reporting staff (wife) says that this wood is still used commercially.
Treated wood produced after 2003 supposedly doesn’t contain arsenic. It’s more expensive than untreated wood, but it takes longer to deteriorate. The debate rages on about the safety of today’s pressure-treated lumber. Being skeptical, I avoid it.
Also avoid old railway ties, they contain harmful creosote. Skip wood that contains lead-based paints or stains because they may leech into your artichokes, zucchinis and everything in between. Food-grade plastic liners can be purchased to line the inside of the bed.
Landscape “timbers” that are made from recycled plastic are easy to assemble and can last for 10-plus years.
Beds made from rocks, concrete/cinder blocks and bricks will get quite hot in the sun and dry out faster than other kinds of beds.
So, what’s a gardening article without a caveat? Sound the alarm and raise the red flag: there may be heavy metals in the ash that is used in making cinder blocks. I wish you luck in finding someone who can confirm the presence of any such metals.
A raised garden bed is usually 10 to 24 inches high. Some people like them higher to minimize stooping or allow for wheelchair access. Such beds can be built with a seating ledge to facilitate weeding and harvesting.
Four feet wide is the most convenient for reaching from the sides and not having to step on the soil.
Length is a matter of preference, but should be long enough to yield a barn full of crops and feed a small nation. Well, at least feed your family.
Raised beds allow better control of soil conditions. Instead of removing the old soil I spread a 3-inch mixed layer of half organic compost and half local topsoil each season. Local soil takes our climate and environment into consideration for growing plants. You will have fewer weeds and the soil will be loose enough for you to pull them out by hand rather than using tools. Some gardeners put down heavy cardboard as a ground barrier for weed control.
Mulch will also reduce your weeding time, regulate the soil’s temperature, retain moisture and add to the soil’s fertility.
I suggest 3 feet of pathway, if possible, so you have space to comfortably work between beds, fences and buildings. To minimize weeds between your pathways, consider organic mulches, straw, gravel, or pine needles.
Raised beds bless you with an extended growing season because they warm up sooner in the spring and stay warmer later into fall than in-ground gardens.
Build your bed in an area where it gets enough (usually six-plus hours) sun for the types of vegetables and flowers you plant.
Drip irrigation uses much less water than hand wands or automated sprinklers.
Add plastic hoops to create bird barriers or row covers.
To stop burrowing monsters hiding under your bed from chomping on plant roots, add hardware cloth to the bottom of the box. If deer are a problem, build a moat. Just kidding. Try deer fencing. En garde. (Sorry).
Schmidt is a Poway resident with over 40 years of gardening experience.
