Improving Garden Soil in Fall

As plants mature, they use up a lot of nutrients from the soil, so putting back some of those nutrients for the next crop is one way to ensure successful gardening every year.  Fall is the best time to add amendments so they have a chance to be broken down by microbes over the winter.

Knowing What to Add

When garden beds are cleared away or perennials go to sleep, take a quart plastic bag, scoop a trowel of soil from five or six areas in your gardens, seal it up and take to your extension office for a soil test.  Or you can find a lab online that does these tests.  The soil test will let you know what you need to add to your garden specifically.


Most plants will thrive in a soil pH close to neutral which is 7 on a 1-14 scale.  So anywhere from 6-8 pH works for many plants.  Some, like rhododendron, azalea, and hydrangea prefer more acid soil. Others do better in alkaline soil.  If your soil is too alkaline, you can add pine needles, peat moss, or elemental sulfur.  If your soil is too acidic, add lime to raise the pH level.

Adding Compost

Whether using your own compost or bagged compost, adding a 3 or 4 inch layer in the vegetable garden and around your ornamental plants will stimulate microbes and other beneficial organisms to refresh tired end-of-season soil over the winter.  You’ll also want to add some compost and a little fertilizer to the holes where you are planting fall bulbs, new shrubs, trees or other landscape plants.

Raw Organic Matter

In addition to adding compost to your vegetable garden, you may want to also add some raw organic matter like grass clippings and shredded leaves plus some manure for added nitrogen.  Cow, horse, sheep, and chicken manure will work.  It can be added fresh in the fall because the ammonia has time to dissipate over the winter.  Beneficial soil organisms will help decompose this material.


Some of the best nutrient amendments for fall application are kelp meal, greensand, rock phosphate, and bone meal.  You can mix these organic materials right into your garden or side dress around plants.  One way to accomplish adding all of the compost, raw material, and nutrients is to mix everything in a wheelbarrow and apply it all together.

This is the last gardening article this year unless you leave a comment below asking for other topics.  Here’s to successful gardens next year.