As late winter days get longer and our imaginations run rampant with the possibilities that still lie dormant in our gardens, this is a good time to consider your garden soil. Your garden’s soil is at the root of everything that happens in your garden. (Yes, the pun is intended!) Healthy soil is an indispensable element to a healthy, beautiful garden.
Healthy soil has some basic characteristics:
a) It holds water, but not for too long
b) It holds air, but not too much
c) It has good tilth – it will clump in your fist, but fall apart readily
If you have ever gardened in clay, you know how frustrating it can be. Even though clay has wonderful nutrients that plants love, clay holds water. For a long time. And that makes it unsuitable for plants that need good drainage. In this type of soil, adding compost and lots of it, will improve growing conditions enormously and increase your plant choices. Basically, however, once you have clay, you will always have clay.
Spring is a particularly dangerous time for clay soils. With its tiny pore spaces, compaction at this vulnerable time can ruin a clay garden. So, it’s important to stay off the soil until conditions are noticeably drier. Every footfall can create an area of compaction from which the clay soil cannot recover. If it is absolutely critical that you get into the garden before it dries, lay down a broad plank to disperse the weight and avoid compaction under your feet.
Although not quite so dramatically vulnerable, clay loam must also be protected from compaction. How do you know if you have clay loam? Grab a fistful of your wet soil and make a ball. Now squeeze that ball up through your fist. Does it form a ribbon that breaks off after an inch or two? Then in all likelihood it’s clay loam. Use the same caution as described for clay soils; stay out of the garden until it dries. (Here’s a link to a good document on the topic of soil structures.)
Sandy loam is less vulnerable to compaction, but it is still wise to be cautious about causing compaction. Truly, the only soil that won’t compact is sand. In sand, compost is also your friend. In truth, compost is a positive addition to any soil.
Fundamentally, it’s important to know that everything depends on the pore space in your soil. That’s where roots breathe, drink and eat. No pore space, no roots. No roots, no plant. No plant, no garden. So, the wise gardener stays out of the garden until it dries. When it’s dry enough, do your soil a favour: lay down some stepping stones, and use those to navigate through your garden from now on.
Protecting your garden soil from compaction is the first step in keeping it healthy, but there are more healthy-soil strategies that we will discuss in future blogs. Please come back!