Improving Sandy Soil: Amending It Right

Sandy soil is one of the major types of soil and has specific benefits and disadvantages. We'll show you how to improve sandy soils!

Sandy soil


People with the wrong types of soils know how difficult it is to grow plants in poor soil quality. Water runs out of sandy soils quickly and the soil lacks nutrients that plants need to thrive. A few steps can help you improve your dry and sandy soils and grow a wider variety of plants in your garden. Let’s delve into this topic and learn what sandy soil is and how you can improve it. 

What is Sandy Soil?

Sandy soil
Sandy soil has a large particulate size and does not clump together well. Source: Aaron Jacklin

Sandy soil is a type of soil that consists of tiny, fine particles formed due to weathering, breakdown, and fragmentation of rocks such as limestone, granite, and quartz. This type of soil can be difficult to grow in because of its low water and nutrient content. The large particles contained in the soil have no pockets to hold water and nutrients, and it is easy for fertilizer or water to flow right through it or be lost through evaporation from warm soil. 

How to Tell if You Have Sandy Soil

Sandy soil is quite easy to detect by its feel and gritty texture. 

To identify if you are working with sandy soil, you need to perform a simple test. For this, you will need to take a handful of sand and dampen it. Next, roll it into the shape of a sausage in your hand. If your soil is sandy, it will start to crumble and fall apart. You will be able to spot individual particles of the soil. 

In contrast, clay or loam will stick together much better. Clay soil will cling together and can be shaped just like the clay we play with as kids. Silty soil has a slippery and fine texture, and will clump but comes back apart easily if squeezed. 

Unlike clay or silt, sandy soil will crumble apart rapidly once you shape it. It may hold its shape very briefly, but not for long. The particle size is simply too large to stick together.

How to Improve Sandy Soils

Good soil on top of sandy type
The topsoil here is full of organic material, with sandy soil beneath. Source: Holy Outlaw

Sandy soil does not have enough organic compounds. As it’s all larger particulate, organic matter is necessary to help it retain water and nutrients. 

Work In Lots Of Rich Organic Materials

You’ll need to amend the soil. The best way to do this is by incorporating compost or composted manure. It is dark, crumbly, and clings together, plus it retains water. Compost also contains plenty of vital nutrients for your plants in its organic material, and as that organic matter breaks down it slowly releases them to your plant’s roots.

Composts made from grass clippings, leaf mold, manure, food waste, and other similar products improve the soil. While adding sphagnum peat moss, coconut coir, or vermiculite can also amend sandy soils, these additions only improve the moisture retention capability of the soil. They do not address the lack of nutrients. 

Apply 3 to 4 inches of well-finished compost or manure over the surface of your gardens and landscape beds and work it into the sandier soil. 

Layer On The Mulch

Compost can also act as a mulch, especially if it’s a bulky compost with lots of larger bits. Spreading a thick layer of compost over your soil slows erosion and helps maintain soil moisture. It’ll gradually decompose and combine over time with your sandy material, dropping from the surface deeper into the bed. Applying more to top it off not only provides nutrients and soil improvement but will keep your plants happy and your beds weed-free.

Grow Cover Crops

Another convenient source of organic matter is growing cover crops. Planting a cover crop reduces weed growth in your garden beds. Later, you cut the plant and let it decompose into the soil. Common summer cover crops include cowpeas, pearl millet, and buckwheat. In winter, you can plant hairy vetch, mustard, and crimson clover. These crops are sown in bed and just as they near the flowering stage, they’re ready to till into the soil.

By tilling them into your sandy soil, you’re incorporating more organic matter. It will hang on to the water for you, and as it decays it becomes its own fertilizer. Plus, they prevent erosion on the surface of your soil, and the plant roots prevent soil compaction.

How to Fertilize Sandy Soil

Sandy field before fertilization
This field, prepared for planting, shows a heavy-sand soil type. Source: agrilifetoday

Any soil type will benefit from the regular application of fertilizer. However, sandy soil tends to have less ability to hold onto the nutrients you’re applying. A slow-release granular fertilizer is generally recommended for sandier soil types to provide continuous small amounts of fertilization.

Before planting, you can work granular fertilizers through the soil. Once the plant is growing, apply the fertilizers to the surface of the soil and lightly scratch them in.

How to Water Sandy Soil

Since sandy soil types drain off excess moisture quickly, you may need to water them more frequently. Providing mulch on the surface will also aid in reducing water loss through evaporation. And, of course, working peat moss or coconut coir through your sandy soil will allow it to hold more water.

When the soil is fully dry, briefly dampen it and then wait a few minutes to allow the water to permeate through the sand particles. Then, do a slow, deep watering with a soaker hose or other drip irrigation method to ensure that the liquid can spread throughout the soil.

Maintain a watering frequency that suits your plants’ needs. Some plants require more than others, so there’s no single method that works for everything!

Best Vegetables for Sandy Soils

Horseradish in sandy soil
A young horseradish plant developing well in a sandier soil type. Source: snaphappykate

Most root vegetables hate overly soggy soils. While sandy soils are not universally beloved, they’re fantastic for growing your root vegetables in. Carrots, beets, radishes, parsnips, potatoes, and many other tuberous or deeply-rooted vegetables adore a sandy bed. These don’t do as well in clay, as they prefer the light and loose texture of sandy soil.

Alliums such as garlic, onions, and leeks all like the soil to be a bit loose and sandy as well. So do many herbs and spices, particularly those grown in Mediterranean climates like oregano, rosemary, and so on.

Other fruits and veggies are able to thrive in sandy soil, too. It may require regular light watering, perhaps as often as once a day, but they’ll still perform admirably. Tomatoes, squash, peppers, melons, and even lettuce can be grown without much difficulty in your sandy soils.

In the end, sandy soil is not a major drawback in the garden. In fact, many plants prefer it to the denser clay types. But improving it to make it more productive is a wise choice for any gardener.