Fall Soil Enhancements

What to give your soil for a successful spring

When the gardening season comes to an end, the average gardener heads for the indoors to hibernate. However, experienced organic gardeners understand that fall is not the time to relax, but a time to work your soil. It is the most important season of the year for soil improvement. What should you put in your soil this fall? There are three types of organic nutrients: finished compost, raw organic matter, and organic nutrients.

Compost
Whether you make your own compost or buy it in bags or have it delivered by the truckload, stock up on as much as you can afford in advance. Every fall, we go through a couple yards of compost (besides what I make in my own bins). It’s piled on a large waterproof tarp, which allows me to keep things tidy while also keeping the compost covered so it doesn’t get soggy or blown away by the wind. My most recent composting assistant is a Gorilla Cart. I keep it full of compost, and it makes it easy to deliver the black gold around the farm.

As you remove spent crops from the vegetable garden, loosen the soil with a garden fork and mix in a 3″ to 4″ layer of compost. While soil temperatures are still warm, microbes and other beneficial organisms will be stimulated by the nutrients and organic matter in the compost. When spring arrives, tired, end-of-season soil will be refreshed and renewed, and ready for your new plantings.

Compost is also required for flower gardens, and will enhance growth and blooms in spring. Keep a good supply of compost on hand as you begin to cut back and clean up your perennial beds. Wherever you’ve pulled out annuals and wherever you’re planting bulbs, add some compost. Apply a 2″ to 3″ layer of mulch around the base of established perennials and shrubs (keeping it back an inch or so from the stems).

Are you planning to plant new shrubs, trees, or other landscape plants? Although opinions differ, I always add a few shovels of compost to the soil that goes back into the planting hole as food for growth.

Organic Raw Material
The soil in your vegetable garden will most likely be fallow during the winter months (unless you’re lucky enough to garden all year). Consider incorporating raw organic matter directly into the soil to increase the amount of organic matter in your soil beyond what you can get from finished compost. What is raw organic matter? Leaves for most.

When adding raw organic matter to your soil, there is only one thing to keep in mind. Beneficial soil organisms that will aid in the decomposition of this material require nitrogen to function. This means that if you don’t supplement the organic matter with some nitrogen, the microbes will begin to deplete the nitrogen in your soil. To avoid this, either mix in some nitrogen-rich manure with the raw organic matter or apply some granular organic fertilizer.

For raw organic matter, I prefer shredded leaves. If you have a leaf shredder, use it. If not, simply mow over the leaves with your lawnmower several times. Another technique is to put a few handfuls of leaves in a plastic garbage can, and pur a string trimmer in the barrel for a few minutes to shred the leaves.

Animal manures (but not those from dogs or cats) are beneficial to the soil. It can be collected in buckets, plastic trash bags, feed bags, or the bed of a pickup truck. The benefit of adding animal manures in the fall is that it doesn’t matter whether the manure is fresh or aged. The caustic ammonia will dissipate over the winter months, leaving behind valuable nutrients and organic matter.

Organic Soil Improvements
Because most organic fertilizers release nutrients slowly over many months, applying them in the fall helps ensure they’ll be available to your plants the following spring. If you can obtain kelp meal, greensand, rock phosphate, or bone meal, do so. You can incorporate these organic materials into your garden (or use as a side dressing around plants) alongside the shredded leaves, manure, and compost. Nitrogen is required for the breakdown of organic material. You can speed up the process by using All-Purpose Fertilizer.

If you suspect that your soil pH needs to be adjusted, autumn is the time to do so. It is best to gradually increase or decrease soil pH over a three- to six-month period. In the fall, add lime to your soil to raise the pH level. If your soil is too alkaline, add acidifiers such as pine needles, peat moss, and elemental sulfur. Remember, unless you already know your soil is too acidic or alkaline, you should always conduct a soil test to determine the pH level before taking corrective action.

Good Soil = Great Garden
Improving your garden’s soil can help it retain water, support healthy plant growth, and protect your plants from diseases, pests, and other stresses. Building better soil is the single most important thing you can do to improve your gardening success, whether you’re a novice or a seasoned pro. And the best time to do it is in the fall!