This is a variety of yellow beets called 'Yellow Intermediate Mangel.' I've thinned them since I took this photo, and the greens were very tasty.

The root of this beet can reach up to 10 pounds. Fortunately, one can harvest them when they reach as little as one inch in diameter. So I shouldn't have any problem growing them in containers. But next time I'll give them a little more space horizontally. Right now, they're crowding the carrots I planted in the back half of this container (not visible in photo).

I've had almost no problem with insect pests. I did find one larvae on a leaf and I just picked it off.

This particular variety keeps well in a root cellar. Other varieties that are good keepers are 'Winter Keeper,' 'Detroit Dark Red Beet,' and 'Long Season.'

Here are the basics on growing beets:

General Info:
Beets are fairly easy to grow. There are few pests or diseases that bother them.

Beets provide salad greens when harvested early, cooking greens a little later, and then roots for cooking, baking, pickling, or in salads.

Location: Full sun or partial shade

When to Sow: Direct sow as soon as soil is warm enough on a consistent basis. (See "Soil Temperature" info below.)

Planting Depth: Usually 1/2", some varieties require a depth of 1"

Plant Spacing (After Thinning): Different according to variety. See seed package.

Soil Temperature for Germination: For most varieties, soil must be at least 55 degrees. Some varieties (for example, 'Pronto Beet') can be sown at 45 degrees. At the high end, most varieties prefer a soil temperature below 75 degrees. Some can germinate at a soil temperature up to 85 degrees.

Days to Germination: 5 - 10 days

Days to Maturity: Anywhere from 55 to 70 days, depending on the variety.

Tips: Don't allow beets to completely dry out at any time or they'll become woody and bitter. Extra watering later on won't remove the bitterness.

See also:
Self-Watering Containers
Growing Swiss Chard
Growing Carrots
Growing Cucumbers