Underfoot, Lofty: Good Soil for Healthy Plants (P. 1/3)

Let’s talk about soil. I made this pitch last spring and since then, I’ve learned more about soil and noticed a lot of interest in it in popular media. (See links below.) So I’m recharging my appeal this year: before we get into our gardens this spring with shovels, stop and consider the soil in your plot and how to protect and make good use of it.

Organic

A simple rule in our organic community garden is that we don’t use any agricultural chemicals. This one’s easy. We all know that products such as Roundup and Sevin aren’t healthy for us or the environment in many ways.

But organic gardening is more fundamentally about supporting nature and working with it. With regard to our soil, even the act of digging into it can mess up its natural beneficial processes. In some ways, less is more. Stop disrupting your soil, and it will thrive and work better for you.

Home Soil

Last fall when I dug a shallow trench to plant my garlic, I felt bad about displacing a handful of earthworms. Those critters were just the obvious living organisms in my garden. A teaspoon of good quality soil is populated with more microorganisms than people on earth. That’s billions of algae, fungi, bacteria, yeasts, protozoa, nematodes, and more. Scientists are only beginning to understand the complex ecosystems in soil and how they support plant life.

Here’s a simplified description of the relationship between your plants and microbes:

  • Plants take in carbon dioxide and through photosynthesis, use the carbon atoms to form sugars.
  • Some sugars are released into the soil through the plants’ roots, providing food for microbes.
  • These microbes, in turn, provide important nutrients right to the root zone of the plant.

Microbes act like home delivery food service. Sounds good, right? Here’s another point to understand: good soil with organic matter holds together in small clumps (aggregates) separated by open pores. Microbes thrive in this kind of environment; in fact, they depend on good soil structure for critical functions. Taking a shovel to it is like bulldozing their natural habitat. And destroying their home means your plants are going to be deprived of the little guys that nurture them. Your plants themselves like good soil structure for other reasons, too.

Soil Care

How can you tell if your soil has good aggregation? A handful of well-aggregated soil has the pebbled texture of cottage cheese. Soil that is poorly aggregated, in contrast, doesn’t hold together at all, or if you gently squeeze it, forms into larger chunks that don’t crumble nicely into pea-sized pieces.

Other bad consequences come from churning up your soil. For example, “tilling soil causes pore spaces to collapse and seal over, causing more rain to run off than sink in.” Your plants aren’t getting that water and worse, water run-off carries away your garden soil. Tilled soil is also lower in organic matter.

I like this description, relayed by Sharon Gensler, the Soil Carbon Outreach Coordinator at NOFA/Mass. “Poor soil is like a mound of flour, which sheds water poured on top rather than absorbing it. On the other hand, water poured over a stack of sliced bread is easily and quickly absorbed. The bread has crumb and texture, with many pours available to absorb and retain the moisture, while the flour is dense with very little porous space for absorption of air or water.”

Last summer, I took over a plot that another gardener couldn’t use. The plot had grown

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Once I pulled all of the purslane from this garden, water pooled on the surface and ran off rather than being absorbed by the soil.

“weedy”  with purslane (an edible plant, though not my favorite), so I set about clearing the entire plot. My thinking went like this: I’d clear the purslane so it wouldn’t compete with my garden plants for water and nutrients, and then I would cover any bare areas with compost and mulch to protect and build the soil.

Once all of those plants were cleared, however, I found I was left with dry, dusty soil that didn’t hold water well. Have you ever had a problem with hydrophobic soil? You might have experienced it when you let a flower pot filled with a peat-based mix dry out. No matter how much I watered the cleared garden, the soil seemed to repel, rather than absorb the water.

I went ahead as planned and covered the soil with compost and wood mulch–which helped with the watering problem, eventually–but I would not have had to remediate so extensively if I had selectively left some of that purslane in place. In many cases, a living root is better than compost and mulch. To be clear, I’m not advocating for letting any weed run rampant in the garden; certainly some weeds will outcompete garden plants. But in this case, I should have thought of that purslane itself as a garden plant–not only because it was edible, but also because it would have been a good friend to my garden, protecting the soil from erosion, supporting microbial life, and helping to retain water.

Bottom Line?

Start with soil! Make friends with the billions of organisms living underfoot, and they’ll do a lot of heavy lifting for you and your plants. Setting the shovel aside is just one way to keep your soil zoo happy. I’ll talk about what I’ve learned about no-dig and other soil-building methods, but up next in Part 2: Good Soil for a Healthy Planet.


For More Info…

From Green America, understanding the complexities of soil.

Interesting fact sheet from the USDA on soil health.

The Zoo Beneath Our Feet, from the Washington Post.

What is humus? From National Geographic.

Got worms? Earthworms can be an indicator of soil health. From MSU Extension.

How to Turn Dirt Into Soil From Yes! magazine, home gardeners share their experiences.

A deeper dive into soil aggregation. From the Soil System Sciences (SSS) Division of the European Geosciences Union(EGU).

 

 

How’d It Grow? Premium Peas

Are you getting ready to plant peas? It’s still too early here in zone 6, but I thought I’d mention this variety while there is still time for ordering from seed catalogs.

Description and Source

Premium is the name of the pea, which can be a little confusing if you go looking for it online since ‘premium’ is also used by seed companies as a descriptor. This particular variety is available exclusively from Johnny’s.

Premium is open-pollinated and resistant to Fusarium Wilt.

Please note that Johnny’s sells both untreated and treated seeds, the latter of which is coated with a fungicide to protect them from diseases such as damping off. When I contacted Johnny’s about the treatment, the representative indicated that treated seeds are not approved for organic growing.

Planting and Growing Notes

Last year on April 1, I sneaked into the garden on that one flashy warm day we had here in MA and got these guys planted in a nine-foot row under a mini grow tunnel (with a plan to remove it as they grew). Using Johnny’s intensive spacing guidelines, I planted them in a 3-inch band, 1 1/2″ apart, around 25 per foot. These peas do not grow tall, and although a trellis is not needed, I set up supports at the time of planting to keep space for other plants and to help make picking easier.

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‘Premium’ also grew well in a pot. Supported on twine and bamboo, they were easy to pick. Following this crop, I was able to fit in a crop of scarlet runner beans.

Soon after I planted them, the temperature dropped precipitously, down into the twenties. And then we had a long spell of cold, wet weather. I’d been hoping that the grow tunnel was going to warm the soil and help them move along, but those pea seeds didn’t budge for nearly three weeks, for so long without a sign that I thought I’d lost them. Around the time they sprouted, I put in another crop of peas in a pot on my front sidewalk, and those guys matured only a day or two later than the ones I planted  on April 1.

Harvest

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After shelling, I had about a pound of peas from a 9-foot row.

Most of them were ready for picking around mid June. Even if I account for that cold snap right after I planted them, they took a little longer to mature than the 51-day average noted by Johnny’s. Still, I was able to get my next crop in the garden easily while they were finishing up.

The nine-foot row in my garden yielded a little more than 1 pound of shelled peas.

How’d they taste? After eating Premium my teens decided that they do like peas after all. The flavor was fresh and sweet, not metallic or bitter, even for ones that I missed and left on the vine a little too long.

The ones that I blanched, froze on a paper-towel-lined tray, and then stored in freezer bags held well for a few months.

Bottom Line?

I’m planting these again in 2019, probably  a week or two into April depending on weather trends. My portable grow tunnel might have saved the peas from rotting, but didn’t warm up the soil enough to make planting worthwhile so early in very cold temperatures.

Though some peas like Bistro may offer higher yields, I’m generally interested in moving things along to fit in a succession of crops in a short time. I hear Strike is another good one to try for early yield.

Best of all, they tasted good and got my teens to change their minds about peas.

 

How’d It Grow? Dara, Wild Carrot

This plant was the biggest happy surprise of last season for me. Many thanks to the grower at Holly Hill Farm who sold me on it at their annual seedling sale.

Dara is an ornamental also known as False Queen Anne’s lace, ornamental carrot, and wild carrot. In my garden, some of the initial flowers on this plant opened up into broad 5-inch blooms, ranging from white to purple-pink to dark purple. Flowers that bloomed later in the season tended to be smaller, though still around 3 inches in diameter.DSC_0203

 

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It’s not a fussy, formal flower. Here it is, mingling with some orange cosmos. I get a bit of shade in my garden, so the Dara grew on the tall side of the standard 36-50.”

Pollinators of all shapes and sizes loved the blooms, and I enjoyed the buzz they brought to the garden so much, I cut only a few of them for bouquets.

Generally, they are a long-lasting cut flower, but some of them drooped right away in the vase and never revived. I learned later from the book Floret Farm’s Cut Flower Garden (which by the way, for locals is currently available through Old Colony Library and Hoopla) that it’s best harvested “when flowers are fully opened and are lying flat.” Older blooms begin to curl up, like umbrellas caught in the wind. DSC_0231

I’ve read dueling information about whether this plant is a garden thug, perhaps because Queen Anne’s Lace, the white flower often seen growing in meadow’s ditches, and scrubby patches, is listed as a noxious weed in some states (not in MA). It might also be worth noting that Johnny’s Selected Seeds specifically calls this plant False Queen Anne’s Lace.

Expert gardener Ken Druse discusses his experience with Dara on the podcast A Way to Garden. Ken–who enjoys this flower, but does take care to contain it– says his self-sown Dara seeds sprout in summer in NJ, overwinter, and then flower the following summer.

Here in New England, Johnny’s Select Seeds calls them an annual and recommends direct-sowing them. I can vouch that the ones I purchased as seedlings sown in a six-cell pack in the spring established themselves fine in my garden and bloomed the same summer. Is it a thug here? I’ll find out this summer.

A few takeaways…

  1. This flower fits in beautifully in casual gardens.
  2. Pollinators love them.
  3. Johnny’s recommends direct-sowing the seeds, but starting them indoors for later transplant also works.
  4. Plant them in groupings for greater effect.
  5. If you’re concerned about them taking over your garden, take efforts to contain them until you see how they behave in your area.
  6. Give them some kind of support to help keep them upright. I used twine and garden stakes.
  7. Dara is not a cut-and-come again flower like zinnias. You’ll get more than one flower per plant (7-15 stems per plant, according to Johnny’s), but it won’t keep producing all season. Still, its season extends a month or more, and multiple, staggered plantings can achieve a longer period of bloom. You may also get a longer blooming period if you keep them cut. I just didn’t have the heart to take them all from the bees.
  8. For best longevity in floral arrangements, cut them after they’ve fully opened. And once they begin to curl up, they’re on their way to seed.