Perennial vegetables, you ask? That's right! A vegetable that keeps coming back, year after year after year…. Sounds too good to be true! But that's how asparagus, rhubarb, artichoke, and horseradish reward your care.
Asparagus will produce for 15 years or more, so choose its site carefully. A sunny, separate bed or a place at the edge of the garden is a good choice. The foliage is tall and ferny, so plant it where you'll enjoy its ornamental quality. Asparagus is more likely to drown than to die of thirst around here, so good drainage is important. Soil enriched with plenty of compost and fertilizer will help maximize its production. Sky carries two-year-old crowns; let the plants grow without harvesting the first year to get them established, then enjoy their bounty each following spring!
Rhubarb can also be enjoyed as an ornamental; its huge, dark green leaves make an architectural statement in your beds. Like asparagus, it likes plenty of compost and fertilizer; however, it tolerates heavier soil and likes lots of water. Rhubarb is almost problem-free; the only maintenance it usually needs is to remove any flower stalks if they appear. Remember that those ornamental leaves are toxic to humans. The stalks, however, have many uses for jams, pies, even chutney. Rhubarb-berry cobbler - yum!
Artichoke is an even bigger guy - it grows as a silvery-leafed 4-6' fountain. (Its close relative, cardoon, is most often grown as an ornamental.) Artichokes are Mediterranean plants: they like well-drained soil and lots of sun. They do best with some winter protection - cutting the plant back to one foot and mulching heavily. In early spring, fertilize; water weekly while those luscious flower buds get nice and plump.
Finally, the REALLY perennial vegetable: horseradish. Frankly, this plant is a renegade: the roots spread vigorously and any small piece will grow a new plant. Plant it in an undisturbed corner or in a container. Horseradish is not fussy about site or soil (obviously!). You can harvest any time after midsummer, but the yields and flavor are best if you restrain yourself until after the first fall frost.
So come in and check out Sky's Flowershed for vegetables that will keep on giving through the years!
Skylights Spring 2006, Vol 20, No. 1
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