Unlike when you store carrots by freezing, I would not suggest blanching beets. Here are my tips:
Harvesting Tips: 1) Keep in mind the maturity dates on the seed packet as a rule of thumb. Most beets are ready in 50 to 70 days.  If you know how wide the tops or how tall the greens will get at maturity, you will know when the beets are read to harvest. 2) Don’t forget that beets still taste good even if they are smaller so you can’t go wrong! 3) Use a gardening tool to loosen the soil around the beet root and then pull them. 4) I would suggest rinsing the dirt off while you are outside.
Storing Tips:  5) Cut the green stems to about one inch above the beets and trim off the roots. Add the leaves, stems and roots to your composter. If you like to eat the leaves, this will be a topic for another day! 6) After the beets dry, put them in a container in the refrigerator. After you have enough beets that were not already eaten, roast and freeze the beets.
Roasting and Freezing Tips: 7) When you are ready to roast the beets, peel them. 8) Cut the beets in chunks or slices. 9) Wrap the beet pieces in aluminum foil to keep them tender. 10) Place them in the oven at 400°F between 40 and 60 minutes depending on the size. 11) Cool the beet pieces. 12) Individually freeze them on a tray. 13) Portion and place a dinner’s worth in a freezer bag or container and then freeze to enjoy at a later date.
If you need any tips on sowing and growing beets,, you are one click away.