If it has holes in it, water will find a way through it. ​

This is true for your tent, your roof, and your garden. In fact, permeability is pretty much the name of the game when it comes to plants and soil.

The rate at which water flows through something else is called permeability. If you’ve ever tried buying a home, you were probably required to pay someone to conduct a perc test. Real estate percolation tests are done to make sure that your house won’t wash away when it rains and that your septic system won’t back up into the living room. A percolation test In the garden can help plants get the water and nutrients they need without drowning. Before we learn how to conduct a perf test, let’s find out why it’s important.

Water in the soil

In the garden, water and air flow in and out of soil, leaves, and even individual plant cells. For a plant, this is the Stuff of Life. The water and air that flow in and out of a plant’s cell walls carry sugars, minerals, oxygen, carbon dioxide, hormones, waste products, and chemicals that allow your plants to thrive or die. [If you’ve ever battled poison ivy or poison oak on your property, you can use a leaf spray that gets absorbed through the stoma (sort of like pores) and carried down to the roots through the phloem. The chemical kills the plant at the roots. This only happens because of the permeability of the leaves.]

Now, too much of a good thing is a bad thing. Without adequate permeability, your plants will drown, suffocate, dehydrate, or starve. Not good. Healthy soil is made up of different size bits of sand, loam and clay. The spaces between these bits are called macropores and micropores, depending on their size. Air and nutrient-rich water pass through these spaces, feeding and nurturing your plants. If the spaces are too small (or absent), plant roots cannot get to the food and air they need to live.

So, how can you, as a gardener, improve the permeability of your soil?
    • avoid overwatering
    • aerate compacted soil
    • apply mulch and compost
    • avoid walking on wet soil

Signs of permeability problems:
    • mud
    • standing water
    • hydrophobic soil
    • chlorosis (loss of green color)

How to conduct a percolation test for soil permeability:

1. Dig a few holes six inches wide and one foot deep.
2. Fill the holes with water.
3. After the holes drain completely, refill with water.
4. If the total drainage time is longer than four hours, your soil has poor permeability.

Ideally, you will want the water to drain at a rate of one or two inches per hour. Of course, sandy soil will drain much faster, taking valuable nutrients with it. You can improve the holding capacity of sandy soils by adding aged manure or compost. If your soil contains more clay, like mine does, you can improve permeability by adding… you guessed it - aged manure or compost! Compost and aged manure add organic material to the soil, creating a wider variety of sizes of both soil and spaces. This variety allows for healthier growth and drainage.

Paved areas can lead to drainage and permeability problems. Permeable paving materials solve this problem by creating a firm surface for walking and parking while still allowing water to seep through. Permeable paving materials are affordable and attractive. They can also eliminate weeds growing up between paving stones!

Do your garden a favor by learning about permeability and composting!

Mud pies may have been a blast in childhood, but your garden will appreciate it if you play elsewhere when the soil is wet.

Soil, silt and clay, mixed with water, creates a slick, slimy ooze that has been used to make adobe bricks, functional pottery, facial masks and exterior stucco. Mud also provides a nutrient-rich habitat to snails, clams and frogs. When your garden soil is muddy, however, it is time for patience. Muddy soil is easily compacted, making life difficult for young (and not so young) plant roots.

Too much of a good thing

All plants need water, but heavy rains and flooding are another story. As soil becomes saturated with water, oxygen is forced out of the ground. Plants need oxygen to survive. Even after the soil dries out, some plants may be stunted and production may be lower. If the soil stays too wet for too long, plants can die. Extended periods of wetness can actually drown the soil, creating a black, stinky mess.

Unless you live in Florida, where sand is predominant, walking on muddy soil can crush those pockets, reducing drainage. Walking on muddy ground can also damage delicate plant roots. Compacted soil requires aeration. Once compaction occurs, you must wait until the soil dries out before repairing that damage.​
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Mud over time

If there are places in your yard or garden that do not drain well, you can dig a shallow trench or install a rain garden nearby. In both cases, water is redirected away from plants. Then, try to determine the cause of your drainage problem. Is a slope causing water to converge on an area? Is more organic material needed? Is there a leaky pipe or sprinkler nearby? It may even be an overflowing septic system. In that case, your family's health could be at risk.

Reduce potential mud problems
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In addition to creating a rain garden or swale, and eliminating water leaks, there are several other ways that gardeners can reduce the potential for problems caused by mud and poor drainage. Continue incorporating aged compost and other organic matter, once the soil is dry. Install moisture-loving trees, shrubs, and other plants in low areas. With all that moisture, slugs and snails will be out in force, carrying diseases and feeding, so putting in some extra time hand-picking these pests can keep plants healthier.

Rather than damaging your soil and your plants' roots, take advantage of muddy days and do something else: sharpen your tools, clean planter pots, or, my favorite, peruse seed catalogs!

Earthworms are worth their weight in gold, horticulturally speaking. They feed on dead and living organic matter. Their squiggly little bodies are basically organic matter processing machines. Food is sucked in through the mouth, coated with mucous, mixed with calcium, and then mashed in the gizzard. Nutrients are absorbed, and everything that’s left is excreted in a paste called casts. Casts contain valuable nutrients that are available to plants, so the more earthworms you have in your soil, the better.

Earthworms also help your soil as they burrow. Their tunnels create passages for air and water. This improves soil structure, aeration and percolation. A single earthworm can produce as much as 10-pounds of castings in a single year if there is enough organic matter available.

Garden shops and websites offer worms for sale but it's generally a waste of money. If your soil is inhospitable to worms, they won't stick around long enough to do your yard much good. Build a hospitable environment and they will come. So, how can you improve the odds of having worms in your garden?
    1    Provide food in the form of compost.
    2    Apply mulch to reduce drying.
    3    Water enough to keep soil moist without being soggy.

Did you know that earthworms are hermaphrodites (both male and female)? Also, did you know that earthworms are born with all of the segments they will ever have?

Wikipedia provided this interesting bit of trivia about earthworms: 

Late autumn and early winter often leave gardens looking bare and unsightly. One way to improve both the appearance and the health of your garden is to use winter cover crops. 

Cover crops can provide a living barrier against the elements, or they can be grown as a green manure, to be cut back before they flower. Cover crops reduce erosion, suppress weeds, and improve soil health.

Even before summer crops are harvested and the last, struggling tomato plant has succumbed to frost, you can plant your cover crops. Any rains that come will help speed their growth. ​