By Victoria Torley

Dirt.

Dirt is something you get under your fingernails. Dirty is smudges on your face and grubby stuff on your knees. Dirt is stains on your clothes and smears on your boots. We do not put plants into the dirt and expect them to grow. Dirt will hold a plant upright, but dirt is dead.

Soil, on the other hand, is alive. Soil is full of bacteria and fungi, worms and bugs, water and minerals, all working to provide a solid base for plants. So how does dirt become soil? Start with the most simplistic
 type of dirt: pure sand.

After all, the first thing that plants need is something to hold them up. Hydroponic gardeners hold things up with perlite, thin sheets of specially prepared Rockwool, vermiculite, or – guess what – sand! So, let’s start with sand.

Sand is boring, sand is dull, sand is, well, sandy. It is also nasty in your bathing suit. But– grab that beach sand, wash all the salt out, and you have the perfect start on soil. Some of that sand is tiny particles of wave crushed shells, so you have already added a nutrient that plants need: calcium.

So, now you have grains of sand and bits of calcium. Now the problem is that water runs right through it. Since plants need water, how do you keep it from flowing away? How does sand become soil?

Here is your recipe. On your left, sand, on your right are leftovers: vegetable scraps from last night’s dinner, egg shells and coffee grounds from breakfast, and a tea bag care of your mid-morning snack. It may not seem appetizing to you, but plants love it.

Now, you could do something creative with all that. You could take all the leftovers and put them in a blender (no, you don’t have to open the tea bag, just pop it in, tag and all) with some water.

Then you could just mix that nasty mess with the sand and let it sit for a few days. Bingo! You have (almost) made soil! Of course, the patient way would be to let all those ingredients on the right sit around for a while and then mix them with the sand, or you could scramble everything together immediately and wait a while. I just like blenders. Your new sand and leftovers mix will even hold water.

But what did I mean about “almost” soil? After a few days, you probably have fungi in your sand/leftovers mix and you will certainly have bacteria. The last important ingredient is worms.

When someone tells me that they have great soil but things don’t grow well, I always have the same question – got worms? 

Worms are a sign of healthy soil. Worms digest material in the soil and their casts and “tea” nourishes it. Worms make burrows that allow air and water into the soil and the borrows make it easier for plant roots to hold onto the soil. Happily, if you put your sand/veggie mix in a hole, the nearby worms will find it.

So get out into the garden. Or go to the beach and grab some sand. I bet good things will happen.

Plant of the week. The genus, Tibouchina (Tibouchina papyrus), includes over 200 species of shrub and they are a common sight in gardens or as road-side plants.

Common, however, does not mean ordinary since this lovely shrub covers itself with flowers much of the year, something I really appreciate.

Tibouchina are easy to grow from cuttings so one plant can supply a hillside. Plant in full sun and protect from severe winds. As a bonus, they are pest and disease resistant, even the leaf cutters leave them alone.

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Find more amazing stories about gardening in Costa Rica on the Costa Rica Garden website. Regarding questions on this article, Ms. Victoria Torley, gardener columnist, can be reached by emailing victoriatorley1@gmail.com.