Beets are adapted to grow in cool temperatures, making them a perfect vegetable to plant both in spring and late summer. They thrive when the days are warm (60 to 70 degrees) and nights cool (50 to 60 degrees). They may go to seed if temperatures drop below 50 degrees for an extended period. Sow the seeds in full sun for the best roots; if you don't have a sunny spot in your garden, plant them anyway as beets still produce lots of delicious leafy greens in partial shade.
Beets grow best in loamy, acid soils with a pH ranging between 6.0 and 7.5. If your soil is heavy clay, rocky, hard, or alkaline, mix in an inch or so of compost. Add a bit of wood ash, if handy, because its rich supply of potassium enhances root growth.
Beets aren't fond of crowds, so when sowing the seeds, plant them about 1 inch deep and 3 to 4 inches apart, or sow them closer together and use the thinnings later for salad fixings. Spread a layer of grass clippings, shredded leaves, or straw around your beet patch to help keep the moisture consistent, this is essential for uniform root growth.
For a spring crop, plant beets as soon as the soil dries out and you can work it, typically from March to mid-May. Where the weather remains cold and wet into spring, wait until April. Beets do transplant surprisingly easily for a root crop, so you can germinate the seeds inside and move them to the garden as soon as the soil dries out in spring.
For a Fall crop, plant beet seeds directly in your garden about eight to 10 weeks before the first expected frost and harvest them in time for the holidays. Fall beets are often sweeter because cooler temperatures as they size up, sugar levels can be higher.
Read more here: https://sowtrueseed.com/blogs/gardening/how-to-grow-beets