White asparagus is produced by denying
light to emerging spears of any asparagus variety. It is
popular in parts of Western Europe, particularly Germany and
Holland, where large spears are produced and peeled prior to
consumption. Specialized systems have been devised in Europe
for the efficient growing and processing of white asparagus. A
very small quantity is consumed in the U.S., most of which is
produced in Europe and air-freighted. Some white asparagus is
currently being produced on a small scale in California, Mexico,
and Peru.
White asparagus is attributed with a
milder flavor than the green, but it has a shorter shelf life
than the green or purple counterparts. The main problem is
possible stringiness or toughness, along with a bitter
aftertaste. Exposing white asparagus to light after harvest
may cause it to begin to turn green or purple.
Discussions with local chefs and high-end
food retailers over the years have led to the speculation that
white asparagus may be a lucrative new opportunity for New
Jersey growers. Since it is relatively rare, and especially if
produced locally, it is perceived as special, and high-quality. The “European” aspect gives it an air of aristocracy. Therefore, elevated production costs leading to higher wholesale
and retail prices may not be a problem.
At Rutgers, we have experimented during
the ’06 and ’07 seasons with the development of a simple,
low-cost system for white asparagus production that is based on
the conversion of fields that have already been used for green
asparagus. A section of an established asparagus field is
chosen before spears begin to emerge, ideally in late March
after last year’s growth has been mowed away. Low tunnels
covered in heavy-gauge plastic film and with removable anchors
on one side are used to manipulate both light and temperature. The system allows easy access to harvest the white spears at
regular intervals at their peak quality which is 6-10”.
All of the white asparagus harvested in
the small RAREC tests was packed into insulated coolers with ice
and brought to the Tre Piani Restaurant in Princeton, NJ on June
1, 2006 and at weekly intervals during June, 2007. The Head
Chef at this establishment is Mr. James Weaver, President of New
Jersey Slow Foods. He agreed to use the product in prepared
dishes served to patrons, then to provide feedback on the future
prospects for the product. He prepared the asparagus primarily
by steaming or poaching, and served either plain or with a
hollandaise sauce. None of the spears were peeled, but the ends
were trimmed prior to cooking and serving.
Overall, growers should expect the same
yields and size classes as they experience in the field for
their green asparagus harvest, since the lack of chlorophyll has
no effect on yield. Earlier in the 2007 season, a larger (~1
acre) test was initiated with a south NJ asparagus grower, but
the field had to be abandoned for white asparagus production
because persistent high winds kept disrupting the low tunnels.
The results of a detailed survey are awaited to gauge consumer and restaurant results for 2007. Mr.
Weaver was extremely pleased with the quality of the white
asparagus provided in 2006. He said that it was much better
than the product he’d sourced from wholesale European brokers,
the difference characterized as “night and day”. The product
had been stored and used for up to five days without any
noticeable reduction in quality. Mr. Weaver voiced a preference
for the “large” size class over “standard” and “jumbo”, but no
differences in patron preference was observed between green and
purple varieties. He speculated that restaurants such as the Tre Piani would utilize 50-100 lbs. of white asparagus per week
during the production season.
White asparagus is both attainable and sustainable for New Jersey growers, but proximity to markets is
crucial due to short shelf life. Only one restaurant market
was investigated, but it is likely, however, that demand will
also exist in such commercial retail venues as Whole Foods,
Trader Joe’s, and Wegman’s. It is anticipated further that
white asparagus will be an excellent item for roadside and
farmer’s direct markets. Wholesale prices in the range of
~$5-6/lb. have been discussed.
Perhaps the biggest unresolved question is distribution. If there are 1,000 targeted restaurants, how is
the product to be supplied to them? Direct store delivery is
ideal, but unrealistic at present for such small volumes. A
network of “specialty terminal markets” where chefs can go to
find high quality, fresh local produce year-round may be an idea
that is coming of age.
