It's more than a difference in variety. Unlike Eurekas, Meyers (Citrus x meyeri) are not true lemons but a Chinese hybrid, most likely between a lemon (Citrus limon) and a mandarin or orange. That parentage gives Meyer lemons a natural sweetness and more mellow flavor than their tangy counterparts – and less acidity. (That's an important fact for cooks to remember in recipes: Meyer juice is less tart.)

A darling of Martha Stewart and Alice Waters, the Meyer – nicknamed "the gourmet lemon" – also has become a favorite of California gardeners. Little more than a bush, the nearly thornless tree stays compact – usually 6 to 10 feet tall, although it can be pruned smaller and grows well in containers. The tree often blooms twice a year and is notoriously prolific. The smooth, rounded fruit has a thin skin like a mandarin and a slightly orange tinge when ripe.

The first Meyer lemon was brought to this country in 1908 by horticultural explorer Frank Meyer, who was collecting unusual plants in China for the U.S. Department of Agriculture.

Today's trees are "Improved Meyer Lemons," offspring of a virus-free clone discovered by Four Winds Growers of Winters in the 1950s and later certified and released by the University of California in the 1970s. Virtually all Meyer lemons in California now trace back to that first Improved clone.

Eureka remains the predominant commercial lemon variety. The "supermarket lemon" bears all year and has fewer thorns than other true lemon varieties.

You may also see these varieties:

Lisbon – A good producer in hot inland regions, this lemon has more thorns and dense foliage on the tree. Once established, it can withstand cold temperatures better than Eureka.

Ponderosa – This lemon-citron hybrid grows mammoth, bumpy fruit – often 2 to 4 pounds apiece – and is grown as an ornamental.

Yen Ben – Smooth-skinned with thin rind and few seeds, this cultivar has become No. 1 in New Zealand and has become a favorite for the export market.

Santa Teresa Feminello – This is Italy's limoncello lemon. Highly productive trees produce very acidic fruit with a high concentration of lemon oil in the skin.

Genoa – Introduced from Italy, it's become a top commercial lemon in Argentina and Chile.

Villafranca – A native of Sicily, this lemon features the best characteristics of Eureka and Lisbon.

Variegated pink – This novelty fruit features green- and yellow-striped lemons with pink flesh. The tree's new leaves are fuchsia pink. It's excellent as a landscape tree with added benefits – fresh fruit.

© Copyright The Sacramento Bee. All rights reserved.

Call The Bee's Debbie Arrington, (916) 321-1075.

• Read more articles by Debbie Arrington