spear a thought for asparagus
Asparagus Plant Management
Outdoors in temperate climates, the
normal cycle of asparagus crop production is to allow the plants to grow
only fern through summer, building up carbohydrate reserves in the
crown. During fall and early winter,
the plants stop producing fern and
the foliage dies back as the crown
goes into dormancy. Once conditions begin to warm up in spring, the
crowns re-activate and start to send
up new spears that are harvested for
a period of six to eight weeks, and
then plants are permitted to go to
fern again for the summer. With a
heated indoor garden, there are several ways the plants can be managed
to either produce spears year-round,
as they do outdoors in tropical
areas, or as a managed system of
forcing spears out of season. Since
asparagus can be grown in a pot
or container, plants can be moved
outdoors for some of the year and
shifted back into the heated indoor
garden once dormant during winter
to force early spear growth long
before any local outdoor crops are
ready for harvest. The application
“there has to be a
balance between the
amounts of shoots
harvested as spears,
and those allowed to
fern to keep the plant
healthy and growing.”
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Maximum Yield USA | January 2014
of heat and moisture will start the
dormant, crown-producing spears
relatively quickly once indoors. At
this stage, green asparagus can be
produced if the plants are positioned under artificial lighting. If
white asparagus is being produced,
a dark room or lightproof covering
over the dormant crowns will ensure
the spears become blanched with no
green colouration. Once spears have
been harvested for around eight
to10 weeks, the grower should stop
cutting new shoots so the plant can
generate sufficient foliage to replenish the reserves in the crowns that
support spear growth.
For a year-round asparagus production system, plants need to be
managed a little differently. There is
a trade-off between harvesting spears
and future yields, or strength, of the
pl [