Answer: To be honest, I think it is too late in the season for the spinach. You can try keeping the soil evenly moist and shading it a bit, but it just may be too hot for it. You can plant it in late August as a fall crop, though. As you've found, watercress, a streambank native, needs constant moisture. You can try keeping it very wet, and see what happens. It has been known to thrive even under the eaves of houses where rainwater drips on it. Keeping it in a container set in a dish of water may allow you to fine tune the moisture and growing conditions, or, if you have a naturally damp spot with a neutral to alkaline soil, you might try planting it there.
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