Maybe I am, but I had some seeds left over from cucumbers
(unsuccessful) and corn (partially successful), so I just planted
them against a white wall for reflected heat.

Even though it's late September in So. Calif. Coastal, it's very hot
today. (In fact, in parts of the area, in the mountains to the
Northwest, the fire season is underway.)

I planted green onions, broccoli and carrots 1-2 weeks ago
and they practically JUMPED out of the ground, so I figured
whathehey, why not try the cukes & corn.