i had a question about the methods for harvesting asparagus, and anyone who knows me i take every opportunity that i have to educate folks. how many folks have thought they were asking an innocent question have been treated to a 20 minute lecture i don’t know, but surprisingly enough folks still keep asking questions. maybe they like it, who know? anyway the point being, below is a pretty basic summery of my asparagus experience.
asparagus is a perennial, which means it comes back year after year, though it has a productive life of about 15 years. those that are growing asparagus for a living usually have fields that are at various stages of life so that if one starts to reduce it’s yield another will be coming on. you can also plant multiple varieties that come on at various times so that you have a longer season. most folks plant hybrid varieties these days, but there are plenty of good open pollinated varieties. i forget what kind we have, it’s been a long time since we started it. most folks these days also only plant male plants, because they don’t spend any effort making seeds, which reduces the overall yield of the plant. we have both, and i get plenty of spears, and i like seeing the little red berries on the plants, it makes them all the more like christmas trees. one other reason is that you might want to grow only male plants is that asparagus beetle larva need the berries to complete their life cycle. no berries no beetles. they have never really been a major problem for me. one other surprise to me is how much the bees love the asparagus flowers. they are small but full of pollen, they go nuts.
asparagus can be grown from seed or you can buy crowns, or you can transplant them from another location (no small task). Growing from seed certainly is much cheaper, but it takes a long time to get the seeds to germinate, and the plants take a long time to get up to transplant size. i grew my plants from seed, and knowing all i know, i would grow them from seeds again. i think that it is just too much of a joy to have grown them from seed to miss out, but if i didn’t have access to a greenhouse i’d just buy the crowns.
buying crowns is a bit more expensive, and if you are growing organically, finding certified organic crowns is no easy task. it does however have a certain amount of instant gratification, and saves you time. asparagus has to be established for 3 years old before you start harvesting, so buying one year old crowns means you have to wait less time to start harvesting. you can get 2 and 3 year old crowns, but they are more expensive, and from folks i talk with they don’t always establish well.
the usually method of growing asparagus is to dig a foot deep trench, place a couple inches of compost or well rotted manure, put the crowns down, spread the roots, cover with just enough compost to cover the roots, and keep the shoots that are developing uncovered, or just slightly covered. as the shoots grow up you backfill will more soil, usually only an inch at a time or so until you have them totally covered. asparagus likes plenty of fertility, i usually top dress them with manure i get from the state fair, or plenty of high quality compost.
since asparagus is a perennial keeping it weed free is very important. i’ve heard of folks that grow their asparagus in sod, and I’ve been thinking about trying to establish dutch white clover under mine, but you still need to keep the weeds down. i feel like one of the main advantages of keeping the asparagus in bear soil is that it comes on earlier. if it were in clover, the soil wouldn’t warm up as quick and i wouldn’t get as early a crop. i get one of the earliest crops in the whole region, and because of that, i can command top dollar (that is if i wanted to sell it, it all goes into the soup kitchen). i usually cultivate every other week, using a rototiller set on the highest setting, or a wheel hoe. the rototiller is certainly faster, but it doesn’t have the quiet joy that is using a wheel hoe. once the fronds are up and open and doing well they pretty much shade out any weeds that would be a problem, plus they are so big and lush it’s hard to get though them anymore. i mulch them once the canopy closes up. this helps keep the weeds down and the crowns protected over the winter.
in the spring i cut off all the brown dead growth from last year as close to the ground as possible, and remove all the mulch. this stuff makes some of the best material from the bottom of a compost pile, make sure you hold onto it. for me this usually takes place in early april. you can also burn the tops off, which is certainly more fun, and dramatic, but my patch is very close to my greenhouse, which i don’t want to risk burning down (i did almost burn the greenhouse down one year, the flames coming with in 4 feet of the plastic, killing several grape vines in it’s path, and turning some irrigation lines into a heap of melted plastic). once all that’s cleaned off i cultivate well and usually see the first shoots coming up in a week or so.
for the first couple years that’s all there is to it, but once well established you get into the really fun stuff, eating. i let my patch establish though 4 seasons before i started harvesting, but in most cases 2-3 years is enough. the older the patch is the more you can harvest, the first year of harvest you harvest for 1 week, the 2nd 2 weeks, the 3rd 3 wks, the 4th for 4 weeks, the 5th for 5 weeks, and every year after that a maximum of 5 weeks per year. if you harvest too much the crowns will not have enough energy to put up enough foilage to put energy into the crowns for next year.
harvesting is best done first thing in the morning, the spears are at their sweetest, and they are the coolest, making for less time to cool down in the cooler. harvesting daily insures that you get to pick the best spears at the peak of quality. i try to time it perfect so that the spears are as big as possible, but have not opened up at all. this takes some practice, as well as paying attention to weather. in warm sunny weather spears grow faster than in cool overcast weather. harvesting can be down by snapping off or cutting. they make special asparagus cutters, i’ve never used one so maybe it would change my life, but i think it would just be one more tool for me to take care of and misplace, simple pairing knifes work fine. Snapping is easy and assures that you don’t damage any spears coming up, but also tend to make for shorter spears. I like to have my spears as long as possible, knowing that the customer is going to cut off the bottom no matter how long they are, assuming that they will be woody at the bottom. If you snap them off, you will be avoiding the woody part, but reducing your over all yield. My preferred method is to cut. when you are harvesting with a knife you need to be very careful and look for any spears that are coming up, often they can be hard to see, as they can be dark purple when they start to come up. looking for this i carefully cut as low as i can cutting away from any spears that are coming up. once i get them all cut i bring them inside, trim the ends off if they have healed over at all, and put them standing up in water, and put them in the cooler. i don’t ever wash them, as i find they don’t keep as well.
that’s all folks, likely more than you ever want to know.