Damping off damping off

After reading farmer Jon's posting in which he mentioned some of his seedlings were damping off, I realized that this was exactly what was happening to my seedlings. I was wondering why my poppy, valerian, and lavender seedlings weren't becoming expectedly big and strong with the warmer sunny weather of the last few days. Instead, they were getting scrawnier and eventually just collapsing and disintegrating, which sounds like exactly what was happening to some of Jon's seedlings.

I think my potting soil was poor. I'd water it, and it seemed to stay moist for a long time. When it finally did dry out, it was extremely dry, crusty and chunky, not fluffy like it was when I first filled the flats. All in all, it didn't seem like a very habitable place for a baby seedling (as nutrient-rich as it may have been). I may also have been watering too often. They say to let the soil dry out completely before completely saturating the soil with water again. This makes the soil inhospitable to the damping-off fungi that like to attack seedlings.

I realized that I really should have sifted my compost rather than just crumbled it through my fingers. I don't know what I was thinking. I guess I just didn't feel like going to the trouble of making a compost screen. So I went to the trouble this morning, and I made a great little sieve (I only needed to make the screen part shown on that page, not the frame it sits on). I found a ½"-gauge screen by the railroad tracks (I actually went there specifically to look for one, too; I also found a perfectly good cooler). I sifted all my potting soil, and already it felt much softer and less chunky.

But I knew I'd need to do more than sift it, because if I grabbed a fistful, it would still stick together in clumps that wouldn't break apart very easily. It seemed I needed the equivalent of peat moss for my potting soil to make it act more like a sponge. But peat moss is a non-renewable resource and its use promotes the loss of wetland habitats. An alternative to peat moss is coconut coir, but it comes from India, so that's out of the question. The more common alternative is vermiculite, but it's mined and its production is very petroleum-dependent, so it doesn't interest me either.

I went back to HtGMV just to make sure they really did say to use one part compost, one part garden soil for making potting soil. Yup, that's what it says. But then I realized that the compost they're referring to is the hypothetical compost that I would have made last year - from vegetable remains, compost crops and yard waste - whereas the compost I had delivered to my backyard seems to be very much manure-based. It's rich, dense and pretty homogeneous. By contrast, compost made from leaves, twigs, stalks and veggie scraps would be (as I recall our garden compost as I was growing up) much more powdery, fibrous, and heterogeneous. Which is possibly why it eliminates the need for a spongy ingredient like peat moss. This is all very speculative, of course.

If only I'd had some of that "other" compost to use for my potting soil! But as luck would have it, today just happened to be one of the city's "Environment Days" where I knew they gave away free leaf compost, and it just happened to be within a 25-minute walk from my house, too. Clearly, it was meant to be. I grabbed the biggest knapsack I had, lined it with a couple oversized plastic bags, grabbed a shovel, and headed down. I got there, and there was barely enough left between the tufts of grass to scrape an oversize load into my knapsack. I'll leave you to imagine how uncomfortable the walk back home was. At least it wasn't raining.

I added the sifted leaf compost to my potting soil, and it seemed to improve it a lot. It had just the texture I was looking for. So I resowed most of my seeds, plus tomatoes, groundcherry, and spearmint, using the new soil (I think it's still within 7 days of the new moon) and we'll see if it works a little better.