When I first interviewed to work at Terra Firma back early February of 1993, it was a warm sunny day and the crew was planting potatoes. It had been a pretty wet winter, and the ground was still muddy and cold. A week later, when I showed up for my first day of work, it started to rain and didn’t stop much for a month. The potatoes never had a chance to sprout, and rotted in the ground.
That potato field taught me several early lessons about farming here. The most obvious was to not put all your faith in the weather you’re experiencing right now. Keeping an eye on the weather is a farmer’s most important jobs, and yet too many of us put other concerns first.
The second lesson was “don’t put all your spuds in one basket”. Since then, we’ve been careful to space out our plantings — not just of potatoes, but of other crops too — to try to avoid similar catastrophes. And over the years, we’ve had our share of crops planted on beautiful days only to be wiped out by rain, cold, wind or heat just a few days later.
Spring is potato planting season in most of California. Potato plants are sensitive to frost. And the tubers themselves are not just prone to rotting in the ground before sprouting as happened to us in 1993; they also begin to cook when the soil temperature is over 80 degrees. This gives us a fairly narrow window for planting. January is too early, and May is way too late. Potatoes are grown by planting pieces of cut potato in the ground. (Despite not being actual seed, these spuds are called “Seed Potatoes”.) The “seed” is grown in cooler areas where they can be planted in late spring and harvested in the fall — ours come from Colorado. We order them in the fall and receive them in January.
Planting your own potatoes from the previous year is a bad idea. Any diseases the potatoes had the year before will be transferred to your new crop right off the bat. “Seed” potatoes are checked by government inspectors before harvest, and any diseased plants are destroyed and the tubers removed from the field. If a field has too many diseased plants, none of the potatoes in it can be sold for seed.
If we plant all your seed potatoes in February and they freeze or drown, we can’t just call up and order more. It’s basically a one-shot opportunity. So, for many years after our 1993 spud disaster, we split our spuds roughly in three and spread the plantings out: One in February, another in March, and the last in April. We would start harvesting the first planting in late May or early June, and finish digging in early August. Each year one or the other planting would outperform the others, generally based on the weather. For years this worked out reasonably well for us.
Sometime after 2015, I started to notice that the April planting of potatoes was no longer producing well most years. It was just too hot in the summer for the tubers forming underground. I remember one year digging up a plant to check on the spuds in July and being shocked at how hot the soil was. Some of the tubers were already soft and rotting — cooked. Beginning the next year, all our potatoes got planted in February and March.
In 2020, it became obvious that our February-planted potatoes were clearly outperforming the March-planted ones. With climate change raging, our springs have gotten shorter here and our summers longer. We’ve been experiencing hot- to very hot temperatures much earlier in the year, and summers themselves have become far too hot for potatoes to succeed. Last year for the first time we planted all of our spuds in February, in two plantings 3 weeks apart. We finished harvesting in June, just as the summer heat got going. It was a huge relief to not see the poor potato vines wilting in the afternoon sun in July anymore.
February is traditionally one of the wettest months of the year in Northern California, but that has become less and less true in the 2020s and this year is no exception. We started planting the spuds yesterday, February 1st, but we easily could have planted them 10 days earlier. January was almost totally dry, and February is starting out the same way. The soil is dry enough right now that it would many inches of rain to rot the potatoes we’re planting, and there is no indication of that happening in the next two weeks. By that point, the spuds in the ground will be sprouting and if it’s not raining, we’ll likely have to irrigate them.
At some point in the future, temperatures will probably rise to the point where potatoes — already a marginal crop some years in our area — are no longer a viable crop at all here. But growers in major spud-growing regions like Idaho and Washington will likely face a more existential threat — as will potato lovers. The Pacific Northwest saw high temperatures last summer that were hotter than any we experienced in this area. The places where agriculture relies on temperate weather are likely to be even more impacted by climate change than areas like ours where it has always been very hot.
For now, there’s a reasonable chance we’ll have a very nice crop of spring potatoes to dig sometime in May. And for the next couple of months, you’ll continue to get freshly dug fall-planted spuds from Full Belly Farm in your boxes. That’s a story for another time.