Feed your soil so your soil can feed your plants

I've been in my garden now for more than 30 years. The first decade was spent establishing the beds and borders, and I worked in seemingly mountainloads of soil amendments such as sphagnum peat, chopped autumn leaves, but mainly compost - spades and spades full of compost.

Over the years, the soil texture has been excellent. But in the past year or two, the soil has seemed finer and lighter in color. Some of my favorite perennials weren't blooming as well as they might. That's when it struck me that I hadn't been taking care of soil fertility very well. And like a field that is planted year after year with a crop, if I don't give something back to the soil, my crops are gradually going to become smaller, less productive and more prone to insects, disease and winter kill.

This isn't a problem with my containers, since I put fresh potting soil in those each year and fertilize them regularly with liquid fertilizer. It isn't a problem with my lawn, either, since a lawn service fertilizes it twice a year.

But the beds and borders weren't flowering well. Some of my vegetables looked downright puny.

The short-term fix was easy: A slow-release, all-purpose granular fertilizer. Osmocote is the most readily available of these, but you can use others. Right before a rain, I simply sprinkled it directly onto the soil, following package directions. Over the next three or four months, it will slowly release nutrients to the plants.

Applying synthetic chemicals like these to my garden definitely help, but they're not the best solution. (They're pricey, too. It cost me about $60 to fertilize my extensive plantings.) Synthetic fertilizers are a little like giving vitamin pills to a person suffering from malnutrition. What that person really needs is regular, healthful meals.

Same with soil. And in the case of gardens, the equivalent of a healthy diet is compost.

Compost is what gardeners call black gold. It does so many almost-magical things for your garden. It improves soil texture, breaking up clay and helping sandy soil better hold moisture. The improved soil texture also makes it easier to weed. Compost adds all sort of micronutrients and microorganisms to the soil. It attracts earthworms, which further enrich the soil by aerating it and leaving behind their castings, which are rich in nitrogen.

I used to have five compost piles, and I gradually reduced that to two to save space. I didn't have the constant pressure of having to empty them out to make way for more incoming yard waste, so I was no longer regularly applying compost to my beds and borders.

So my strategy is to first add at least one more compost pile for my garden on a medium-sized town lot, about a quarter acre in size. And I need to once again practice a golden rule: When planting anything, add at least 1 or 2 spadefuls of compost to the planting hole. If I'm planting an area with seeds or small seedlings, spread 1 to 2 inches of compost on top of the soil and work it into the top foot of soil.

I also need to resume my old practice of 'top dressing” with compost. That is, spread 1 inch of compost on top of the soil in various beds and borders, or spread two to three spadefuls around large plants, like at the base of a shrub.

If you have mulch in place, you can rake it back and set it aside in a wheelbarrow or on a tarp. Then spread the compost and top with the reserved mulch.

I'm looking forward to getting out there and working in the compost piles more often. It's rewarding to watch weeds and autumn leaves and kitchen scraps break down into beautiful, black, rich-smelling compost. It's even more satisfying to be rewarded with abundant flowers, fruits and vegetables in my garden.

Veronica Lorson Fowler is co-publisher of The Iowa Gardener website at theiowagardener.com.