Gardener’s Guide to Soil Amendments (2024)

FAQs

What is the best amendment for garden soil? ›

Compost is the most commonly used organic amendment, but other products are available. Over time, organic matter improves soil aeration, water infiltration, and both water- and nutrient-holding capacity. Many organic amendments contain plant nutrients and act as organic slow release fertilizers.

Mostly, perennial roots do not reside in the planting hole for long, so the time that amendments would be effective is very short. Since amending can also harm some plants if done incorrectly, University of California does not recommend the practice, neither did Harris for trees, shrubs and vines.

The best time to amend your soil is in the fall. The winter gives time for soil microbial life to break down organic matter and digest other minerals, making them available to the plants. If you didn't amend in the fall, still do it in the spring. Get a soil test.

Coffee grounds have a high nitrogen content, along with a few other nutrients plants can use. In compost, they help create organic matter that improves the ability of soil to hold water. It's best to add coffee grounds, not whole beans, to compost.

Soil amendments are meant to improve your soil, but unnecessary amendments can backfire and cause more problems than they solve. Lowering soil pH too much can create toxic conditions. Raising soil pH too high sets off a chain of nutrient imbalance. Even organic matter can cause problems if used too much.

Excess application of amendments onto land can lead to negative impacts on soil quality and crop production caused by salt effects alone. Salt levels are gauged by a manure's or soil's electrical conductivity. Salt content in soil can also be expressed as exchangeable sodium percent.

Amending Poor Soil With Lime, Ash, Manure and Sulfur. Adding lime, poultry manure, or wood ash to your soil can make it more alkaline and raise the pH to a healthier level. Elemental sulfur can help make soil more acidic. Once you've tested your soil, you may have some work in front of you to get it ready for planting.

Its purpose is to reduce evaporation and runoff, inhibit weed growth, and create an attractive appearance. Mulches also moderate soil temperature. Organic mulches may be incorporated into the soil as amendments after they have decomposed to the point that they no longer serve their purpose.

The best way to amend soil in an existing garden is by top-dressing the bed with an inch or two of compost each season. The compost will break down, improving the soil structure and fertility. Plus, you'll perk up your perennials.

Is potting soil a good soil amendment? ›

POTTING SOILS are specially formulated for containers, to enhance root development and provide excellent drainage. They generally should not be used to amend garden soil.

Effective mulches include shredded hardwood bark, pine needles, coarse compost, and shredded native tree trimmings. Mulching helps hold moisture in the soil, controls weeds and buffers soil temperature. It also protects and stimulates microbes and enriches the soil with nutrients as it decomposes.

Mulching. Mulching is an integral part of no-till gardening. Cultivators add mulch in layers over time to work more nutrients into the soil, insulate the roots from extreme temperatures, and reduce weed and pest infections.

PerFect Amendment is a soil additive with a high concentration of patented beneficial Streptomyces on an iron and humic acid carrier that when added to the soil produces healthier plants that more effectively resist stress, and reduces the need for excessive watering.

Loamy Soil: The gold standard for most gardeners, loamy soil has a balanced mix of sand, silt, and clay. It retains moisture while ensuring good drainage and is rich in nutrients and organic matter.