Several years ago, I made these beds by mixing equal parts native sand, peat moss and composted wastewater sludge. That first year was phenomenal, and I had to actually throw away some zucchini, cucumbers and tomatoes because I could not give away all of the extras. For the last two years, my cukes have died before even producing. I still get some tomatoes, but not nearly as many, and many of the heirloom plants did not survive this year. Got good production from one Early Girl plant, but that's about it.

So, what should I do to fix the soil now? The cuke bed has a 7' trellis above for the plants to grow on, so rotating crops is not practical there. I have tried swapping tomatoes and squash to opposite ends of the beds each year, but still no luck. Soil amendments? Ideas? Thanks.

Seems like I read somewhere about planting a winter cover crop of hairy vetch and tilling it under in spring to add N to the soil. Anyone tried that?

Have you been mixing in at least 2 inches of compost each time you plant the bed? If not, that's the problem.

I have added some compost, but maybe not nearly enough.

The soil pH was normal for around here, around 8.0-8.2 or so. We have alkaline desert soil. Tap water gives about the same pH!

2) Drainage. Dig a hole 1 foot square and 1 foot deep and fill that with water. After that water drains away refill the hole with more water and time how long it takes that to drain away. Anything less than 2 hours and your soil drains’ too quickly and needs more organic matter to slow that drainage down. Anything over 6 hours and the soil drains too slowly and needs lots of organic matter to speed it up.

3) Tilth. Take a handful of your slightly damp soil and squeeze it tightly. When the pressure is released the soil should hold together in that clump, but when poked with a finger that clump should fall apart.

4) Smell. What does your soil smell like? A pleasant, rich earthy odor? Putrid, offensive, repugnant odor? The more organic matter in your soil the more active the soil bacteria will be and the nicer your soil will smell.

5) Life. How many earthworms per shovel full were there? 5 or more indicates a pretty healthy soil. Fewer than 5, according to the Natural Resources Conservation Service, indicates a soil that is not healthy.
to see how good that soil is. These will guide you in what to do.

I can do the jar separation test easily enough.

My soil drains too quickly, I'd put money on that. Part of the reason I added peat initially. When I mixed the soil, it was to a depth of about 12-16". The main garden plot is against a rock wall which is retaining about 6' or so of earth. The lots behind me are lower. So the soil stays drier than I would like if I am not watering. But maybe I need more organics in it.

I think it will pass the clump test okay but will confirm.

It smells like dirt, not foul, not too sweet, just like dirt.

I will try the earthworm test. I know I have them, but have not counted them.