I’ve told you what a bear our clay soil can be. It’s especially tough on small seeds, like carrots and onions and almost any herb. Surprisingly, though, most seeds are pretty tough: there’s a lot of energy needed to break out of the tough shell and sprout, and even more needed to break through this clay soil of ours. I try to help by keeping the soil moist, or by planting things in shaded conditions to prevent the bed from baking in the sun, but it’s still hard work.
I’ve mentioned before that we bought the farm from the original owners. Actually, we got it from the son of the original owners, and he was 89 at the time and had lived here since he was three. This was a thrifty family: nothing was thrown away (that I could tell, anyway; we filled a 20 yard dumpster with such “treasures”). Well, we’re thrifty too but I do draw the line at packrattery. However, there is one item I saved from the dumpster: a whole bunch of burlap potato sacks. These were 50# bags for seed potatoes, most dating, from evidence of their tags, to the early 1970s. And I have found many garden-related uses for the things.
Cut a bag open and lay it atop a newly-seeded bed of carrots and parsnips, as shown here: keep the bag moist and voila! almost every seed has a chance to sprout. Granted, not everyone has old burlap sacks lying around (or do they?). I think this trick would work with old sheets or towels, too; you just need to take a peek pretty frequently to make sure you’re not squishing the sprouts.