The Kitchen Garden
Ode to Compost
Dig in when the mood strikes
By Jan Leitschuh
April is a month to stir the winter-sluggish soul. Soft temperatures and sunshine tempt us out into the yard. Bulbs, blossoms and shoots poke forth in the garden.
An ancient craving takes root: Turn up some soil and plant something.
Here in the Sandhills, our sandy soils can be worked earlier than those with more clay-based underpinnings. Tilling the tight, wet clay characteristic of other areas of the Piedmont too early can result in virtual pottery — clumps and chunks of garden not conducive to deep root structure or drainage. It’s hard to wreck the loose soil structure of our well-drained, sand-based soil. So, we can get to it as soon as the mood and temperature strikes.
But we need to do some critical soil preparation first.
Our unique Carolina Sandhills is an area about 10-35 miles wide within the state’s southwestern coastal plain, a unique region that bleeds down into South Carolina and Georgia. Strong winds from the last glaciation kicked up sand dunes from the shallow seas of the area — putting the “hills” in Sandhills.
It’s no accident the Sandhills was the last area of the state to be developed agriculturally, but peaches, tobacco, blueberries and cotton eventually thrived alongside the longleaf pine and wiregrass. Over time, area farmers learned how to manage sand’s natural tendencies and lower fertility to grow an agricultural bounty.
We kitchen gardeners can, too. Sandy soils have several pluses but need a little love. In some cases, a lot of love.
The East Coast is blessed with plenty of rainfall in a year’s time. This bounty also tends to wash minerals down into the deeper levels of the soil. This descent is accelerated on sand, as you might imagine. This is one reason that our sandy soils here tend to be quite acidic.
Our sandy soils also drain so well that when summer’s heat bakes, we find our seeds drying up and our sets needing daily watering. Skip a day and your plants might stress and drop blossoms — no blossoms, no veggies.
Vegetables need a deep and well-drained soil with adequate moisture, organic matter, and a much gentler pH. Sand has some of these plusses.
Our sandy soils are deep and well-drained, so good news there. Roots can penetrate easily. Sandy soils also warm up earlier than clay soils, so heat-loving plants can go in somewhat earlier.
Sand’s negatives include difficulty holding moisture and nutrition. Luckily, there is a simple solution: loads and loads of compost.
Organic matter, broken down, will loosen the tightest clay and “fatten” the fastest-draining Candor sand. Compost helps sand hold more water. Digging the soil is a dream, easy. And the decomposition process of organic matter feeds the soil biome, adding nutrients as it further breaks down the organic matter.
Compost also captures the nutrients we might apply. It helps hold soil fertility and manage the pH. This is especially beneficial in the case of, say, nitrogen, which may otherwise wash down into the water table. Why not hold on to what you paid for, and let it benefit the plant?
At Cottage Garden Farm, fertility and compost start in the fall. I beseech my landscaper husband to bring home bags and bags of the autumn leaves he scoops up for clients who want to discard them.
My favorites are crape myrtle and maple leaves, since their small size and tender composition break down easily. Whole oak and magnolia leaves are too waxy to break down quickly, and layers of them can form a mat that smothers the plants beneath. But, run over these with the mower and chop them into bits and the tough leaves break down much quicker. I dump these on the garden, around the fruit trees and blueberries each fall. They cover the soil, protect the roots and feed the worms before breaking down into lovely soil. Tilling the garden in spring is a pleasure, seeing the rich dirt turning up. Four inches of fall leaves are more than enough.
Grass clippings are also useful if you know they have not been sprayed. I tend to not use these in my vegetable garden, where I grow food I might eat. I use them around ornamental trees and such. But, with all the Bermuda grass grown in this area, you might be adding weed seeds. Experiment in a small area if you have access to some.
Do not use uncomposted sawdust, fall leaves or straw right now because as it breaks down, it will rob the soil of nitrogen and, consequently, starve the plants of this essential nutrient. These need to be piled to compost.
On other occasions we have planted a cover crop in the fall. Vetch, winter rye and crimson clover send their roots down deep, “digging” plenty of organic matter into the garden all by themselves. Many studies have shown the benefits of keeping roots in the garden over winter — they hold soil and provide places for the soil biome to colonize and expand. Come spring, if you can bear to weed-whack down the gorgeous crimson clover blossoms, you have added “green manure” or even a mulch to your garden, depending on whether you till it or not.
If you have done neither last fall — and now it’s spring — it’s time to haul in bags of compost. Some local businesses offer compost by the scoop if you have access to a truck and strong backs for unloading. Dump your coffee grounds directly into the garden. Start a compost pile — there are many good how-to resources online.
What about the abundant horse manure in this equestrian area?
It’s a valuable resource, and I’ve loved it, but it pains me to acknowledge it is not without problems.
Has it composted? You don’t want it too fresh, to damage plants. Ask the owners if they spray their fields for broad-leaved weeds — a persistent herbicide often used that can wreak havoc with your garden for years. Sometimes, even if the owners don’t spray, the herbicide can come in via the hay.
Finally, the harsh acidity of our sand. Compost helps here too. If you have limed your garden appropriately, compost will help stabilize the pH.
How do you know if you need lime, or another common soil deficiency here, potassium?
You probably need it, unless you are growing blueberries. But the only way to know for sure is to test your soil. The Agriculture Extension Soil Conservation program in your county offers free (April-October) or very low-cost (November-March) soil test kits. You may even be able to have the kit mailed to you. Then simply follow the directions and mail it to the enclosed address at NC State, or drop it off at your local extension office. They will mail or email your results and the staff/master gardener volunteers at the extension office will help you interpret and develop a plan to correct any problems.
So, give in to that urge. Turn that soil, spade your compost into your garden area. Toss in some seeds and sets. You are participating in a spring ritual as old as agriculture itself, one that does the body, and soul, good. PS
Jan Leitschuh is a local gardener, avid eater of fresh produce and co-founder of Sandhills Farm to Table.