Asparagus, native to Europe, North Africa and western Asia, has been the great herald of spring since Roman times. Root clumps called crowns push up thick tender shoots which may grow more than 6 inches a day.
Growers send crews into the field every day to cut those that are the right size to market.
Finally the roots become exhausted and the shoots they send are thin and fibrous. At this point the grower abandons the field and leaves the plants to "fern out", mature and gather energy into the roots for the next harvest. For the summer they make lacy green fronds (like the related asparagus fern) and in the fall they set red berries, turn yellow and dry.
The ancient Romans were very fond of asparagus, and they knew how to cook it. One writer described in a recipe that it should be "cooked just for moments, like asparagus". Louis XIV of France had special greenhouses constructed so he could have asparagus all year. Today asparagus has been carried worldwide and it even appears in Asian stir fries. Because it fetches a good price it has become a major export crop for some countries.
- Peru (Sep - Dec and year round) is the second largest asparagus grower. About 35% of the crop is green asparagus for export to the U.S. while nearly all the rest is processed into cans and jars and shipped to Europe. An increasing amount of fresh white asparagus is being shipped to the U.S..
- Mexico (Dec - Apr and year round except May) is the third largest grower with the entire crop being green asparagus, nearly all shipped to the U.S. where some is transshipped to Japan.
- United States is the fourth largest grower and by far the world's major importer. U.S. exports are small with most going to Canada and some to Japan and Switzerland.
- China is by far the largest grower of asparagus. Nearly the entire crop is processed into cans and jars and shipped to Europe and worldwide, but almost none to the U.S. where green asparagus is favored.
- Spain is Europe's largest producer followed by Germany and Greece. Nearly all is white asparagus.
White asparagus comes from the process of etiolation (http://en.wikipedia.org/wiki/Etiolation) , which is the deprivation of light. Dirt is kept mounded around the emerging stalk, depriving it of light. The plant cannot produce chlorophyll without light, thus there is no green color to the stalks.
White asparagus is considered to be slightly milder in flavor and a bit more tender than green asparagus. All varieties and colors may be used interchangeably in recipes.
White asparagus is the same plant as green, but it's grown with a high pile of soil or mulch over it or tented with plastic sheeting. Since it sees no light it doesn't develop chlorophyll, but it also develop a fibrous skin so it is generally peeled.
White asparagus is the choice of Europe where very little green asparagus is consumed. Germany is the largest and most enthusiastic consumer of asparagus in Europe and has been increasing production, particularly grown under plastic sheeting for early harvest.
White asparagus has little flavor compared to green. Chefs like it, I think, because it provides body with almost no flavor to interfere with their most delicate sauces. It has to be cut rather short as well as peeled because the base is very fibrous.
The most commonly available white asparagus in California is from Peru, 7 inches long and 0.45 inches diameter - a size called "Standard". Large, Extra Large and Jumbo are also listed but I think those sizes go to restaurants. Standard and large are PLU #4522, Extra Large and Jumbo #4523.