Temperature is key in cooking and baking, just as it is in raising the wheat we bring to you.
Spring on the farm doesn't announce itself with calendar certainty. It arrives in arguments, a warm week followed by a frost, mud season one day and frozen ruts the next. After 125 years of farming this land, our family has learned that the air temperature outside the kitchen window is only part of the story. The real conversation happens six inches underground.
Soil temperature is key on our farm. It helps Mike and Alex decide what we should look at planting first, which ones wait on the shelf for a few days, and which ones we'd lose entirely if we pushed too hard against the season. Understanding it isn't just farming knowledge. It's the kind of slow, attentive relationship with land that regenerative agriculture is built on.
Why Soil Temperature Matters More Than the Calendar
Every seed is a biological system waiting for the right conditions to switch on. That switch isn't triggered by the date on a calendar or even by how warm the afternoon feels, it's triggered by the sustained temperature of the soil surrounding the seed.
Seeds need soil warmth for two reasons. First, the enzymes that break down the seed coat and initiate germination are temperature-sensitive. Below certain thresholds, those enzymes work too slowly, and the seed either germinates poorly or rots in wet, cold ground before it gets a chance. Second, beneficial soil microbes; the fungi, bacteria, and other organisms that help young roots absorb nutrients, are only active above certain temperatures. A seed planted in cold soil might technically germinate, but without its microbial partners, the seedling struggles.
On a regenerative farm like ours, where we think about the whole ecosystem of the soil rather than just the crop in isolation, this matters enormously. We're not just planting seeds; we're inviting them into a living community. That community has to be awake and ready.
How We Measure It
A simple thermometer pushed six inches into the ground tells us more than any weather forecast. We did not have a highly sophisticated soil thermometer this season, but we are working on that. Mike took readings in the morning, when soil temperature is at its daily low, because that's the number that matters most. If the overnight low in the soil is warm enough, the seed is warm enough, even when afternoon temperatures climb.
We take readings in multiple spots across the field too, because soil doesn't warm uniformly. Low-lying areas and different soil types hold cold longer. A field that reads 50°F in one corner might still be at 42°F in another.
For most spring planting decisions, we're watching for a handful of key thresholds: 38–40°F, 45°F, 50°F, and 60°F. Each one opens a new door.
The 40°F Threshold: Hardy Crops That Go In First
When the soil hits a sustained 40°F, the first seeds can go in the ground. These are our cold-tolerant crops, the ones bred over millennia to handle shoulder-season conditions.
On our farm, this means:
Oats. Oats germinate reliably at 40°F and actually prefer to establish during cooler conditions. They're among the first things we plant each spring, often in late March or early April here in Minnesota.
Rye. Of all the grains we grow, rye is the most cold-tolerant and arguably the most forgiving. It will germinate in soil as cold as 33–34°F, though we wait for a sustained 38–40°F to give it a strong start. Rye's cold hardiness isn't just a convenience, it's a tool. We plant rye as both a grain crop and a cover crop, and its ability to establish quickly in cold conditions means it's protecting the soil surface and putting down roots while other fields are still too wet to touch. As a grain, rye produces a dense, earthy flour with a complexity that sets it apart from modern wheats. It also conditions soil beautifully, with a deep fibrous root system that breaks up compaction and feeds organic matter back into the profile when it's terminated.
Hard red spring wheat. Spring wheat is planted in spring, unlike winter wheat, which goes in the ground in fall and overwinters, and it germinates well once soil is in the 40–45°F range. On our farm, hard red spring wheat is a heritage-leaning crop with deep regional roots in the northern plains. It produces a high-protein flour with strong gluten development, making it well-suited for yeasted breads and traditional loaves that need structure. The protein content of the grain is directly influenced by how the crop establishes: a clean, vigorous germination in properly tempered soil sets up a stronger plant that draws nutrients more efficiently through the season. Planting into cold, wet soil compresses those early roots and can shorten the season's potential before the plant is even an inch tall.
Red Fife wheat. Red Fife deserves its own moment. It's one of the oldest named wheat varieties in North America — a heritage grain with a lineage that traces back to Scotland in the 1840s and arrived in Canada in the 1840s before spreading across the prairies. It largely disappeared from commercial farming through the twentieth century as modern high-yielding varieties took over, but it has been carefully preserved and is now experiencing a quiet revival among farmers and bakers who value flavor and history over uniformity. Red Fife germinates well at 40–45°F but is more sensitive to soil conditions than rye or hard red spring wheat. It wants a well-prepared seedbed, not compacted, not waterlogged; and benefits from the kind of attentive soil management that a regenerative approach provides. In return, it offers a depth of flavor that modern wheats rarely match: nutty, slightly sweet, with a complexity that carries through into the baked loaf.
Cover crops and soil-building species. Field peas can also go in at or near 40°F. On a regenerative farm, these serve the soil as much as the harvest — fixing nitrogen, protecting bare ground, and feeding the microbial community while we wait for warmer conditions.
The risk at this threshold is impatience. It's tempting to push in more seeds when that first warm week arrives. But 40°F soil in early April can drop back to 35°F with a cold snap. At that point, seeds sit dormant and wet, prime conditions for fungal rot. We wait for sustained warmth, not a good week.
The 50°F Threshold: The Soil Comes Alive
Fifty degrees Fahrenheit is a turning point. This is where microbial activity in the soil increases meaningfully, where earthworm populations start moving toward the surface, and where a wider range of crops can germinate with confidence.
This is when we plant our buckwheat. Buckwheat is particular, it doesn't tolerate frost at all, and it germinates best between 50°F and 70°F soil temperature. On our farm, buckwheat is central: it's what we stone-mill into the fresh flour that goes into our baking mixes, our pancake and waffle blends, our brownie and pizza crust mixes that we are developing. Getting the planting timing right is everything. Too early and a late frost kills the tender seedlings. Too late and the crop rushes to set seed before the grain is fully developed.
Millet is also a 50°F crop, and it's equally important to us. Our millet flour is the other half of many of our blends. Like buckwheat, millet is frost-sensitive and benefits from warm soil to germinate vigorously. The two crops often go in within the same week on our farm, which means their timing is tied together in our planting schedule.
We will also start to gear up for planting our non-gmo corn and non-gmo soybeans.
The Deeper Lesson: Listening Before Acting
What soil temperature teaches, more than anything, is the value of waiting for readiness rather than forcing a timeline. The ground has been building warmth since late winter; slowly absorbing solar energy, stabilizing, preparing a home for seeds. When we push ahead of that process, we don't gain time. We lose it, through replanting, through weak stands, through the stress of seedlings fighting conditions that aren't ready for them.
Regenerative farming is, at its heart, a practice of working with natural systems rather than against them. Soil temperature is one of the clearest signals those systems send. Learning to read it — and to trust it — is one of the first and most lasting lessons this land teaches.
The seeds know when it's time. So does the soil. We've learned to listen to both.