Soil Health and Microbes: The Foundation of BRIX

A single handful of healthy soil can contain billions of living organisms, or soil microbes—bacteria, fungi, nematodes, etc.

These guys are microscopically tiny, but they carry a huuuge impact.

Soil microbes break down organic matter, cycle nutrients, and support plant roots—all of which helps plants grow strong and healthy. Combine a flourishing population of these mighty microbes with nutrient-rich soil and you get dahlias (or any plants for that matter) that are more resilient to environmental stressors and more resistant to pests and disease. Apparently your dahlias would also be more aromatic (if they had a scent to begin with) and more nutritious if you decided to eat them (haven't tested this and don't recommend that you do either).

To put it all simpler...

Happy microbes + nutrient-rich soil = resilient, thriving plants.

So how do we make microbes "happy?"

Well, they're a lot like kids.

• Feed them: Sugar is their favorite—plants naturally provide it through root exudates. Another favorite? Organic matter like compost, leaves, straw, and manure that provide a slow feed as they break down over time.

• Protect them: Keep the soil covered year-round with plants or mulch to shield them from soil temperature swings, help retain moisture and reduce evaporation.

Here on our farm, we use several different practices to try and care for our soil's microbes so they can in turn, care for our dahlias. I'm sure as the seasons go on, we will continue to refine our practices and add more blog posts about it, but here's where we're at today.

Our Farming Practices That Support Soil Life

• We use dried molasses at planting. We mix a bit of dried molasses in our planting holes for a quick source of sugar (microbial food) during the time when plants are establishing roots that will then take over that job.

• We cover our dahlia beds with straw mulch during the growing season. Once our dahlias have popped out of the ground, we cover the soil all around them with straw (organic matter). This mulch supports soil microbes in several important ways: it buffers the soil against temperature swings, it helps retain moisture and reduce evaporation, annnnd it slowly feeds microbes as it breaks down. We use wheat straw cause it's widley available here, but when I grew in Georgia, we used what was widely available there—pine straw.

  
  

• We use leaf mulch to nourish our dahlia beds in the off season. Leaves are nature's original soil cover. In addition to regulating soil temps and helping to retain moisture like our in-season straw mulch—leaves are more nutrient-rich. They break down faster than straw and they do a better job at supporting beneficial fungi in the soil. You probably already guessed it, but just like straw, as leaf mulch breaks down it also feeds the microbial life.

  
  

• We are experimenting with cover crops. Remember the part above where we talk about how microbes' main food source is the sugar that plants release from their roots? Makes sense then to have roots in the ground as much as humanly possible throughout the season—enter cover crops! This will be a whole new post, but suffice it to say that we have no bare soil on our farm. If we're not planting in it right away, it's planted with a cover crop to protect and nourish the soil until we're ready to use it.

  
  

These practices don’t force growth. In other words, they're not "fertilizer." They instead, support the microbes which in turn supports the plant.

What We Avoid Matters Too

I don't wanna spend too much time here cause this information is widely available, but just as important as what we do at Dahlias & Dogwood is what we don’t do.

• After we prepare a fallow bed, we don't till the ground. Excessive tilling destroys fungal networks and disrupts microbial communities.

• After we prepare a fallow bed, we don't use synthetic inputs. Synthetic inputs (conventional fertilizers and pest / disease control) can provide short-term gains but often at the cost of long-term soil life. I add "after we prepare a fallow bed" because the only time we use an herbicide on our farm is to terminate the existing alfalfa so we can create a new growing bed. Our local extention office told us it was either this, or we'd have to till repeatedly until our soil structure was that of powdered sugar. No thanks.

  
  

How Caring For Soil Life Translates Into Higher BRIX Levels

So how does supporting soil microbial life lead to higher BRIX? When soil microbes are cared for, they get better at doing their job—making nutrients available to plant roots. Well-nourished plants photosynthesize more efficiently and produce more sugars, which they send back down to feed those microbes. As that underground partnership strengthens, BRIX naturally begins to rise.

In the next post, we're going to talk about the important role of soil tests and how they play a significant role in a thriving microbial community!

Stay tuned...