Medania is a good all round variety, very winter hardy and fairly slow to bolt.. New varieties pop up all the time, I do three sowing a year for outside, one in late February with a quick growing one like Tarpy F1, another in April with a slower to bolt variety like toscane or medania and then end of July usually medania and also for overwintering in the greenhouse and under cloche ,one sowing start of September.
I never direct sow spinach, always module sow under cover, use three or four seeds per module then plant out three weeks or so later as small plants. If planting when it's cold use fleece. Or you can sow two seeds per module then thin to the strongest and have bigger leaves. Multisowing is good for smaller leaves that you can eat raw as salad