Blenheim and Freestone Apricot Trees

Freestone Versus Clingstone

• Freestone apricots are fruits where the flesh breaks cleanly away from the pit when opened. "Clingstone" indicates the opposite trait -- the flesh clings to the pit with stringy fibers. For drying or canning apricots, freestone varieties make the process much less labor intensive. Freestone fruits can be easier to eat, as well, because there's none of the stringy flesh around the pit to get caught in the teeth.

Blenheim Apricots

• Blenheim is by far the most widely planted apricot variety in California, where most commercial production occurs. It is also known as the "Royal" apricot and is cold hardy only in USDA zones 7 and 8. To set fruit, it requires about 400 "chill units," measured as the number of hours between 32 and 45 degrees each winter. It is a freestone variety with the classic apricot flavor and aroma and can be used for canning, preserving or eating fresh.

Varieties for Northern Climates

• Apricots have a tendency to flower at the first sign of warm weather in late winter or early spring. All too often, cold weather and late winter storms coincide with the flowering period and ruin the crop for the year. Blenheim is well-suited to the mild climate of California's central valley, which rarely sees spring frosts. However, apricot breeders have developed a few freestone apricots that can withstand the winter temperatures and spring frosts that are common in northern climates. The "Canadian White Blenheim" and "Harglow" apricot were both bred in Canada for these traits. These two freestone varieties are known for excellent flavor and are hardy in USDA zones 4 to 7 and 5 to 9, respectively.

Low Chill Varieties

• Another limiting factor in growing freestone apricots is winter chill. Places like Florida and southern California are ideal for apricot production because spring frosts are rare to non-existent, preventing the damage of the early flowers that limits apricot production elsewhere. However, most freestone varieties need more winter chill than these climates provide. Blenheim is a fairly low-chill apricot, but "Katy" and "Goldkist" are more appropriate for truly subtropical climates. These two freestone varieties require only 200 to 300 winter chill units and can be grown in USDA zones 7 to 9.