|'Colorado Preserving' is an heirloom variety of citron watermelon. This is a melon generally used for preserving, or pickling. It does well in the U.S., better than some of the larger varieties. These small, round melons have thick walls and a mottled rind. The seeds are red with black speckles. Texture is like a cucumber. Watermelons generally do best in warm climates. Cool weather will not produce good fruits, but some of the adversity of cool weather can be overcome by starting seeds early indoors, and transplanting them out at the height of summer. Plastic groundcovers are highly recommended to increase soil temperature in the spring, and rowcovers will help the crop ripen in the fall.