Your ultimate guide to healthy garden soil

A thriving garden starts from the ground up — literally. Healthy soil is the foundation of a productive and beautiful garden, providing essential nutrients, proper drainage and the right balance of air and moisture for plant roots to flourish. Whether you’re preparing a brand-new garden bed or revitalizing existing soil, understanding its composition and how to improve it will set your plants up for success.

University of Georgia Cooperative Extension consumer horticulturist Bob Westerfield provides guidance on ensuring your garden soil is ready to provide fruitful vegetables this summer. Follow these essential steps to get your garden soil in top shape.

Before digging in, do you have these essential garden tools?

Start with a soil test

Before planting, it’s crucial to test your soil to determine its nutrient levels and pH. Soil tests reveal what nutrients are already present and what needs to be added for optimal plant growth. Lawns and ornamental areas should be tested every two to three years, while vegetable gardens benefit from testing every one to two years. Results typically arrive within four to six days after the lab receives the sample.

Most vegetables thrive in slightly acidic soil with a pH between 6.0 and 6.5. If your soil is too acidic, apply dolomitic lime to neutralize it while adding beneficial magnesium and calcium. However, avoid adding lime to already neutral or alkaline soil (pH 6.5 or higher), as it can make essential nutrients less accessible, leading to stunted growth, yellowing leaves and poor fruit production. Since lime reacts slowly, mix it into the soil two to three months before planting.

Learn how to take a soil sample from UGA Extension expert Jason Lessl in “Soil Testing for Home Lawns, Gardens and Wildlife Food Plots.”

Testing your soil is always the first step to successful gardening. 

What does healthy soil look like?

Regardless of soil type, the key factors for a thriving garden are high fertility, good drainage, ease of tilling and deep topsoil. Avoid areas infested with persistent weeds like Johnsongrass and nutgrass, rocky sites or locations with a hardpan layer.

Healthy soil should contain plenty of organic matter and support beneficial organisms like earthworms and microbes, which aerate the soil and break down organic material into plant-available nutrients. Since most roots grow in the top 8 inches of soil, maintaining healthy topsoil with organic amendments and avoiding compaction is essential.

Prepare your soil early

If you didn’t plow or spade your garden soil in the fall, do so in early spring as soon as the ground is dry enough to work. To check, mold a handful of soil into a ball — if it crumbles when pressed with your thumb, it’s ready. 

To start preparing your garden bed where your vegetables will eventually be planted: 

1. Turn the soil to a depth of 7 to 8 inches, incorporating compost or garden soil if needed. 

Pro tip: If incorporating large amounts of undecomposed organic matter, sprinkle nitrogen (e.g., ammonium nitrate) over it before turning it under. This speeds up decomposition and provides nitrogen for soil organisms and plants.

2. Rake the soil soon after turning it to prevent excessive drying and maintain good texture. For small-seeded crops, a finely pulverized surface ensures easier planting, better germination and a more even stand.

3. Ensure good drainage by avoiding compacted or waterlogged soil.

Checking soil texture and drainage

Check soil texture

First, wet a handful of soil and squeeze it in your fist.

Clay-heavy soil forms a tight, slippery ball.

Sandy soil crumbles easily and feels gritty.

Loamy soil holds together loosely but crumbles under slight pressure — this is the ideal balance.

Check soil drainage

First, dig a hole about 12 inches deep and fill it with water.

If the water drains within a few hours, your soil has good drainage.

If water remains after 24 hours, your soil may be compacted or too clay-heavy, requiring organic matter or raised beds to improve drainage. Adding sand to clay soil will not improve drainage.

Boost your soil with organic matter

While you can’t change your soil type, you can improve its structure, moisture retention and nutrient availability by incorporating organic matter. Because organic material decomposes quickly in Georgia’s warm climate, regular additions are essential.

• Compost kitchen scraps, straw and leaves to replenish nutrients.
• Incorporate organic material like livestock manure or shredded leaves during fall soil prep.
• Sow cover crops like crimson clover, rye or vetch if you’re not planting vegetables immediately. Before the next planting season, turn cover crops under and add nitrogen for best results.

UGA Extension expert Bodie Pennisi provides in-depth guidance on composting at home in “Composting and Mulching.”

Choose the right fertilizer

Fertilizers supply essential nutrients for plant growth. They are labeled by their nutrient content, such as 10-10-10 (10% nitrogen, 10% phosphorus and 10% potassium). For most vegetable gardens, these three common fertilizer grades work well:

• 10-10-10: Balanced for a wide range of crops.
• 6-12-12: Ideal for root vegetables and phosphorus-loving plants.
• 5-10-15: Suitable for many garden vegetables.

Vegetables fall into three categories based on fertilizer needs: heavy, medium and light feeders. Grouping crops by nutrient requirements simplifies fertilization. Always base fertilizer application on soil test results.

Plan your planting for success

A successful garden requires more than just planting — it takes strategy, Westerfield noted:

• Follow a planting schedule. Start cool-season crops like lettuce, cabbage and peas early, and wait until after the last frost to plant warm-season vegetables like tomatoes, peppers and squash.
• Mark your rows. Use string and stakes to keep rows straight, ensuring optimal spacing and organization.
• Use proper planting techniques. Large-seeded crops like beans and corn should be planted in furrows, while smaller seeds like carrots and lettuce require finely prepared soil.

Protect your plants

Once your vegetables are in the ground, take steps to protect them for a successful season:

• Mulch with straw to retain moisture and prevent soil crusting. Always verify that wheat straw or other materials you put in your garden were not previously treated with long-acting herbicides.
• Transplant healthy seedlings for a strong start.
• Use row covers to shield young plants from extreme temperatures.
• Deter pests by installing chicken wire fencing or, for areas with a heavy deer presence, consider installing a taller, more permanent fence.

See UGA Extension resource “Garden Fencing” to learn about recommended fencing options.

Get ready for a bountiful harvest

By investing time in soil preparation, you’re setting your summer vegetable garden up for success. Healthy soil leads to stronger plants, fewer pests and bigger harvests.

For more resources and advice, explore UGA Extension publications on soil health, composting and vegetable gardening.