Published February 25th, 2014
One of the most frustrating things gardeners face here in southern Ohio is clay soil. Hard and gooey. Glue in spring, brick in summer. For some reason, weeds don’t have a problem growing in it, but vegetable plants, fruits and landscape ornamentals hate it. Not to mention how it sticks to your shoes and tools, making any garden task a chore.
You can improve your soil dramatically by mixing in organic ingredients like mushroom compost, peat moss, or potting soil. Plants breathe through their roots, so the lighter and fluffier your soil the better plants grow. The spongy soil allows plants to breathe, making it easier for roots to spread and water to reach the roots instead of running off.
The downside of turning your soil into a sponge is that water can be trapped around the roots for too long, causing them to rot. “Dig a hole, make a bowl” we like to say. If excess water can’t drain away by gravity, your plants will likely drown.
Most vegetable gardeners make a lot of extra work for themselves by tilling large plots and keeping them weed-free, just to allow space to walk between the rows. Walking on the soil just packs it down again, particularly if it’s wet. Ideally you could concentrate the tilling and soil treatment just where the plants are, and never walk there again.
The answer to all this is raised bed gardening. Build boxes that sit on top of the ground, fill them with fancy soil, and never mind tilling all the space between boxes. Suddenly there’s less weeding, less bending over, and no more soil compaction around your plants. Tall boxes even discourage rabbits. Excess water can seep out the bottom.
Raised beds can be plain or fancy. You can customize each box with the ideal soil and fertilizer for the exact plants you’re growing in it. Concrete block or stone are ideal, but you can build nice raised beds with used railroad ties or pressure treated lumber.
It’s important to fill raised beds with light, fluffy soils. Not only do the plants do better, but well-drained soils don’t burst your boxes by expanding when frozen or wet. The more compost or peat moss, and the less “topsoil” or heavy sand, the better. Some raised bed gardeners add vermiculite or perlite to make the soil light and fluffy. Vermiculite and perlite are “rock popcorn”; flakes of fluffy featherweight rock that’s been puffed up so it holds lots of air. Mushroom compost is another vital ingredient, with trace minerals and plenty of organic nitrogen. We sell both in our nursery.
For acid-loving plants like blueberries and strawberries, we fill our raised beds with “Pine Magic”, a shredded form of pine bark that has the perfect acidity, texture and drainage. It’s the same stuff that commercial growers use to make custom potting mixes for growing in containers. One benefit of Pine Magic is that is has no weed seeds at all. Each year we top off our raised beds with a few inches of fresh Pine Magic, so we NEVER have weeds in our blueberries and strawberries. Talk about easy.