I found Swiss chard grows easier and faster than Spinach. It can also tolerate higher temps than Spinach. When my spinach bolted the chard just kept growing. I even think it germinates easier for seedlings. I was growing Swiss chard bright
lights, I find it a little pungent going to try large ribbed dark green to see if it has a milder taste next. Also trying Asian spinach to see how it does.
Garden Vegetable seeds Varieties S-Z by Ferry-Morse, Discounted Every Day at HomeHarvestSeeds.com