Soil and water

Gardeners share their top tips

Clay soil is found in many American gardens, but it is not a hospitable home for all plants. If you’re getting your garden ready for summer or want to grow flowers or vegetables, you might struggle.

There are, however, ways to make it a friendlier environment for beautiful flowers or tasty produce. Below, two experienced gardeners share their secrets for transforming clay soil, with a day’s work and lots of organic matter.

What Is the clay soil?

Clay soil is made up of fine mineral particles and little organic matter. It’s a heavier soil that tends to stick together and because there is no space between the particles, the soil does not drain.

“If you’ve noticed that water tends to puddle on the soil rather than soak into it, chances are your soil is clayey,” according to Donald Loggins, the original late gardener of the first community garden in New York, Liz Christy Community Garden. .

Soil that’s more than 50 percent clay particles is called “heavy clay,” Loggins said. Newsweek. You can identify it because it sticks to your shoes and gardening tools like glue, forms large clods that are hard to separate, and scabs and cracks in dry weather.

The ideal soil for gardening is loamy, a mixture of sand, clay, intermediate mineral particles and organic matter. It will drain well and have good nutrient retention.

Advantages and disadvantages of clay soil

Amber Scott Freda, a New York-based landscape designer, said Newsweek that because clay soil retains moisture longer, it can prevent plants from drying out.

Plants such as conifers tend to grow well in this type of soil, she said, while species from more arid climates such as succulents, rosemary and lavender are used to growing in soils lighter and won’t like being wet for so long.

“Vegetables and annuals don’t like clay soil because it’s hard for their small roots to grow in such dense soil,” she added.

Loggins said, “Clay soil is prevalent in many parts of the United States, and it can be very problematic if you’re trying to grow a flower or a vegetable garden.” In clay soil, vegetable roots struggle to find their way and spring flower bulbs tend to rot during the winter.

Soil with sprouted seeds. Vegetables struggle to grow in clay soil because their roots cannot break through the dense material while spring flower bulbs tend to rot in the wet winter.
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How to Improve Clay Soil

Improving your soil will take a little work, Loggins warned. Most jobs only need to be done once, but annual maintenance is required.

You have to add a good dose of organic matter to the soil and let nature do its job. According to Freda, you can mix clay soil with gypsum, compost or pine bark to make it lighter and more airy.

You can also lay several inches of mulch over the clay soil and let it gradually break down and improve the soil. “Leaves are nature’s best mulch, so if you can resist removing leaves from your flower beds every year, they will gradually decay and improve the soil naturally,” she added.

It’s best to tackle an entire bed at once, rather than individual planting holes as needed, Loggins said.

“If you dig a planting hole in clay soil, then lay a plant in and amend well only the soil you use to backfill, your plant will be happy for a little while. But you’ve done nothing more than create an in- ground flowerpot.

“Eventually the plant will begin to send up roots which will be stopped in their tracks when they reach the clay walls of the planting hole. You will end up with a root-bound plant that will not grow as tall or as healthy as it does. should.”

Loggins recommends adding 6 to 8 inches of organic matter to the entire bed. These can be grass clippings (as long as they haven’t been treated with chemicals), shredded leaves, rotting manure or compost.

After spreading your organic matter, mix it into the top 6-12 inches of soil using a shovel or tiller “if digging is too hard on your back.” Your garden will look several inches taller than it was, but the beds will settle as the organic matter decomposes.

How to Break Up Clay Soil Quickly

Break up the soil with a hoe or garden fork 5 to 6 inches into the ground. You can use a tiller if strictly necessary, but be aware that this type of powered tool can kill worms and other vital soil organisms.

If the clay is particularly hard, it may help to spread a small layer of sand over it before adding the organic matter.

How to Improve Drainage in Clay Soils

Adding compost will improve drainage. Loggins said you should do this when the soil is dry because working in wet clay is messy and will compact the bed even more.

Compost “not only helps with soil structure,” he explained, but the glomalin compound created by mycorrhizal fungi in compost “binds the small clay particles together into aggregates with a waxy coating, creating thus more space between them for air and water to flow.”

Preparing clay soil for the vegetable garden

If you want to grow vegetables, it is best to work the organic matter deep into the soil, as the roots will find their way there, and to do this before planting.

“You can plow as deep as a tiller will go, or dig sections of a bed at a time up to a foot deep, work in the compost, then replace the soil and do the next section. In the years to come, just work the surface, as the organic matter you’ve worked deep in will decompose quickly when it comes to the surface,” Loggins said.

You can also increase organic matter in clay soils by planting cover crops. “These are crops planted as you prepare beds, for a season or a year before, or during fallow periods between annual crops such as flowers and vegetables. They consist of small grains and grasses such as buckwheat, ryegrass and oats,” he said..

Legumes such as clover can benefit the soil by “fixing” nitrogen from the air for use.

How to take good care of the soil

Freda thinks the key to a beautiful, healthy garden is to treat your soil with compost. “It’s what nature has done since the dawn of time, and Mother Nature always knows best.”

His simple advice is “to add several inches of compost to the clay soil each year and mix it well with the existing soil until the soil measurably improves.”

Man handling the soil
Man handling the soil. The best way to improve sticky, dense clay soil is to mix in some organic matter and let nature do its thing.
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