This year my farm is beginning an adaptation project for spinach. We’ve been growing individual varieties of spinach for the last eight seasons here in Corbett, OR, and we’ve had a lot of challenges. We suspect one of the main issues is the heavy symphylan populations that our farm deals with. Symphylans are a soil-dwelling arthropod that can cause severe crop damage in our region, as they eat the tender growth tips of many germinating plant roots. At times we have a decent harvest, other times our spinach will germinate and then not grow much beyond the seedling stage; at other times we can’t see any germination at all. There are also very few known solutions for symphylan infestations, and larger commercial growers have been known to abandon infested fields. Our hope is that the landrace adaptation methods can help to develop our own genetically diverse spinach variety that can coexist with the symphylans, and thrive in our specific context.
Beyond the main goal of developing symphylan resistance, we’d like to prioritize flavor, yield, bolt-resistance, dual-season use (spring and fall), and overall performance in our cool and damp conditions. Through direct seeding, providing no supplemental fertility, and minimal weeding and watering, we are also selecting for traits that grow well under the simplest and least labor-intensive methods. Our hope is that over time we can share our seeds and contribute to a community supply of food crop seeds adapted to the Portland, OR region.
The plan is to direct seed 1600 spinach seeds in spring (around 4/15), and 1600 seeds in the fall (around 8/1). We’ve selected seed from varieties that have performed better for us, varieties popular among our local farmer community and the greater Pacific Northwest, and the mix provided by Going to Seed.
As expected, the spinach crop failed to produce a good leaf harvest, due to the prevalence of garden symphylans. Although none of the individuals produced a thriving leaf crop, some seemed to show a little resistance/resilience, and we were able to save a good quantity of seeds.
We were interested to see some survivors right beside others that died off, suggesting possible genetic resistance to symphylans in some varieties. We also noticed that individuals with the red trait seemed to have a higher survival rate. We are expecting a better harvest with the upcoming fall sowing, and we look forward to planting our saved seed in 2025.
Classic symphylan symptoms: irregular germination, yellowing of leaves, very sluggish growth, plants eventually die off
We are finishing the first year of our adaptation spinach project. As expected, our spinach crop hugely struggled to thrive with the heavy symphylan populations on our farm. However, there were some survivors that produced seeds, which may perform better next year.
After a spring crop with mixed results, we had higher hopes for our fall-planted crop. Unfortunately the fall planting also failed to thrive. In past seasons we have observed less symphylan activity in summer and fall, after the initial cool and damp spring weather passes. However this season there seemed to be extended symphylan activity through the season. Initial survivors of the fall planting also remained stunted and didn’t grow well, a classic symph-tom. But there are a very few second-round survivors going into the winter which could have some valuable genetics for future generations.
Next season we’ll try out all of the saved seed from this year, and see what happens. If we continue to have huge losses from the symphylans, it could be time to give it up and pivot to a similar substitute. We are also hoping to do more experimentation with natural strategies to control the symphylan populations.
