Both a delicious vegetable and a decorative addition to the garden...asparagus.
We usually treat vegetables as though they were annual plants. We plant seeds or small transplants in the spring and follow their progress until they've reached the stage we want, which could be production of lettuce leaves, carrot roots, or fruits of tomatoes. At the end of the season, we remove whatever's left of the plant from the garden and prepare for our next crop.
There are a couple of notable exceptions to this customary path. A very few vegetables are actually perennials and we treat them as such.
One is the artichoke, where we harvest the bud that would become a flower if we left it on. It's kind of a thistle, and if you like those big purple-blue thistle flowers, you can forget the edible part and use it as a perennial flower. The leaves aren't what I'd look for, but some people find them interesting.
Asparagus is another one of these perennial vegetables. Anybody who's heard me lecture on vegetables knows that I think this is a seriously underrated crop for Southern Nevada.
Think about it - aside from trees, how many plants provide a crop every year for 20 years or more? Asparagus does. One bed can produce spears annually as long as it's moderately well tended.
When I say 'spears', I'm talking about the shoots that come up in early to mid spring. When the plants are young, the shoots are pretty thin, about 1/4 inch in diameter, or thereabouts. As the years progress, the plant produces stems that'll be 1/2 inch thick, or even bigger.
The spears need to be harvested early, while they still look like what we call asparagus. If they aren't, then they burst into leaf. Have you ever seen the houseplant we call 'asparagus fern'? That's a close relative to the vegetable asparagus. In fact, what we eat is the stem that'll become leafy - very fine, and I think, pretty, leaves. These lovely fronds can get several feet tall. Now - wouldn't a tall display of asparagus fronds be nicer to look at than the concrete block walls that surround so many of our homes?
Great - so what makes this such a terrific idea for Southern Nevada (or anywhere in Nevada, for that matter)?
Well, think about our soils for a moment - they're pretty alkaline, and many plants don't tolerate that well. The soils here tend to be fairly salty, since this area was a shallow ocean, eons ago. The water left, but the salt remains. It takes a remarkable plant to withstand a salty soil, and asparagus is one of them.
And then, the soils in the southwest often have high levels of the element boron. In small amounts, this is vital for plants. In very small amounts. Once there's more than about one part per million, many plants begin to suffer, but not asparagus. It's not terribly sensitive to our high boron levels at all.
Finally, it's a drought tolerant plant. And, in a desert, that's essential.
Asparagus does have its requirements, of course. For it to be a success, it needs relatively rich soil, so before putting it in, mix a good supply of compost into the soil. And, while it'll survive drought, it needs ample water to thrive. Like every other living thing.
If you decide to try asparagus in this New Year, find a spot where you'll be able to keep it for a long time. If it can get bright light, particularly in the early part of the day, then it's got a chance of meeting your expectations.
There're several different varieties, so it's worth looking around for them. Some of the old favorites from the northeast, the Jersey giants and the Washingtons, don't seem to be quite adapted to the high temperatures here. You have to be ready to harvest the spears almost as soon as you see them, or else they just leaf right out. A good reason to put the bed in a place where the leaves will look good - say between the concrete block wall and a bank of annual flowers, for instance.
Some varieties remain as shoots longer than the older cultivars - new ones like 'Atlas' and 'Purple Passion'. You should be able to find these, at least in the catalogs. What you'll plant won't be seeds, but crowns, which look like masses of roots, rhizomes and buds. The package'll have planting directions.
It's not too early to choose where you want to place your new asparagus bed. This is a cool season crop, meaning that it should get in the ground before the middle of March.
You won't be harvesting this year, or maybe even the first two years, although you'll pretty asparagus ferns.
This is a long term investment, but wouldn't you love having the chance to eat asparagus fresh from the garden for the next two decades?
For KNPR's Desert Bloom, this is Dr. Angela O'Callaghan of the University of Nevada Cooperative Extension. Happy New Year.