||Well-drained, deep sandy loam.
||6.0 to 6.7
||Cool (60 to 65° F).
||Average; a flush of spears often follows a
||One-year crowns, early spring.
||18 inches by 4 to 5 feet; or in wide beds of
three rows with plants 18 inches apart in all directions.
||Hardy perennial, should be mulched in autumn
in areas of Arizona where the soil freezes.
||Medium-heavy feeder, high phosphorus and
potassium and organic matter at planting; annual nitrogen in
late winter or very early spring; may sidedress after harvest;
benefits from yearly topdressing of compost.
Asparagus is a perennial vegetable which will live from 12 to 15
years or longer. It is one of the most valuable of the early
vegetables and is well adapted to freezer storage. During the
harvest period (traditionally spring, but see below for summer
harvest instructions), the spears develop daily from underground
crowns. Asparagus does well where winters are cool and the soil
occasionally freezes at least a few inches deep; it is considered
Start asparagus either from seed or from one to
two-year-old crowns. For fastest results, crowns purchased from a
respectable nursery are recommended. There is risk of disease from
less reputable dealers. Starting plants from seed requires an
extra year before harvest. Seed may be started in peat pots; they
are slow to germinate, so be patient. Seedlings may be
transplanted in June. Crowns are usually shipped and set out in
March or April.
Choose a site with good drainage and full sun. The tall
ferns of asparagus may shade other plants, so plan accordingly.
Prepare the bed as early as possible and enrich it with additions
of manure, compost, bone or blood meal, leaf mold, wood ashes, or
a combination of several of these. In heavy soils, double-digging
is recommended. To double-dig, remove the top foot of soil from
the planting area. Then, with a spading fork or spade, break up
the subsoil by pushing the tool into the next 10 to 12 inches of
soil and rocking it back and forth. Do this every 6 inches or so.
Double-digging is ideal for the trench method of planting
asparagus since a 12 inches deep trench is usually dug anyway. The
extra work of breaking up the subsoil will be well worth the
effort, especially in heavy soil. The trench is dug 12 to 18
inches wide, with 4 to 5 feet between trenches. The same method
may be used in wide-bed plantings, with plants staggered in three
rows. Mix the topsoil that has been removed with organic matter
and spread about two inches of the mixture in the bottom of the
trench or bed. Set the plants 15 to 18 inches apart, mounding the
soil slightly under each plant so that the crown is slightly above
Crowns should be of a grayish-brown color, plump and
healthy-looking. Remove any rotted roots before planting. Spread
the roots out over the mound of soil and cover the crown with 2 to
3 inches of soil. Firm well. As the plants grow, continue to pull
soil over the crowns (about 2 inches every two weeks) until the
trench is filled. Water if rainfall is inadequate.
Asparagus shoots or spears should not be harvested the
first season after crowns are set. Harvest lightly for 3-4 weeks
the second year. The fleshy root system needs to develop and store
food reserves to produce growth during subsequent seasons. Plants
harvested too heavily too soon often become weak and spindly and
the crowns may never recover. An extra year is added to the above
schedule for asparagus started from seed; i.e. do not harvest at
all the first TWO seasons, and harvest lightly the third.
When the asparagus plants are in their fourth season, they may be
harvested for eight weeks per year.
Harvest spears daily during the 8 week harvest period.
The 6 to 8_inch spears are best, and should be cut off just below
the soil surface. If the asparagus is allowed to get much taller,
the bases of the spears will be tough and will have to be cut,
cutting too deeply can injure the crown buds which produce the
next spears. Blanched asparagus is a gourmet item; to blanch
(whiten) the spears, mound soil around them or otherwise exclude
light from them so that chlorophyll is not formed in the stalks.
When harvest is over (after 8 weeks), allow the spears
to grow. Asparagus has an attractive, fern-like foliage that makes
a nice garden border. Some gardeners prefer to support the growing
foliage with stakes and strings to keep them tidy. In high-wind
areas, it is a good idea to plant the rows parallel to the
prevailing winds so that the plants support each other to some
There are several ways to extend the harvest period of
your asparagus planting. One method is to plant at different
depths (3 inches, 4 to 6 inches, 6 to 8 inches, 8 to 10 inches) .
The shallow plantings will come up first and can be harvested
while the deeper plantings are just forming. This method will
result in a slightly longer harvest, but may result in some plants
being less vigorous than others.
Another way to extend the harvest for a few weeks is to
remove mulch from half of the asparagus bed. Leave the mulch on
the other half. The exposed soil will warm up more quickly, and
the crowns will sprout earlier. This process may be speeded up
even further using black plastic, but be careful not to encourage
growth too early, as heavy frost can make spears inedible. Remove
mulch from the second bed when spears begin to appear.
A third technique for extending asparagus harvest has
been the subject of university research and is highly recommended
for home gardeners who have plenty of space. Plant double the
amount of asparagus needed for your household. Harvest half of the
plants as you normally would in spring, then allow the foliage to
grow for the rest of the season. During the early harvest period,
allow the ferns to grow in the other half of the asparagus
planting. Then, cut the ferns in the second half in late July.
This causes the crowns to send up new spears, which can be
harvested umtil late in the season. If rainfall is short in
summer, it will help to water this bed for good spear production.
A light mulch will help keep the soil surface from becoming too
hard for the shoots to break through easily. If using this method,
harvest the spring bed only in spring and the fall bed only in
fall! Otherwise, you risk weakening the crowns.
In all asparagus plantings, cut the foliage down to
2-inch stubs after frost when the foliage yellows, before the red
berries fall off. Four to six inches of mulch made of compost,
manure, leaves or other material added at this time will help
control weeds and add organic matter and nutrients. In warm areas,
withhold water in October and November to make ferns go dormant
(turn yellow). Remove dried tops in early winter before new
||Rust - use resistan varieties. Fusarium
||Asparagus beetles, cutworms, armyworms,
||Weak, spindly plants and/or too few spears
from too early or too heavy a harvest; crown rot or poor
production from inadequately prepared, heavy soil.
HARVESTING AND STORAGE
|Days to Maturity:
||2 to 3 years.
||Third year spears; cut off just under soil
surface when 6 to 8 inches tall, before tips begin to
separate; use or refrigerate immediately.
||3 to 4 pounds per year, per 10- foot row.
|Amount to Raise:
||6 pounds per person.
||Process or refrigerate immediately in
||Can or freeze.