I live in Mexico in what I consider to be zone 10 or ll.
Asparagus is grown commercially here.
Why do so many "experts," including many who sell the plants, think it needs a chill period and cannot be grown in zones higher than Zone 8?
katiebear
Asparagus in hot zones
Texas A&M University has a growing plot of asparagus which is apparently doing VERY well from what a witness told me. I wonder if it is a variety they developed or just a selection?
I think most of our wintertime asparagus in the grocery stores here is grown in Mexico or South America.
I don't think it's that asparagus needs a chill period, but that it needs a dormant period. Have you checked to see how the asparagus is being grown in Mexico?
They may be using a system similar to that used in other warm, tropical countries. Here's an article from New Zealand: http://www.maximumyield.com/article_v10n4_year-round_asparagus_production.php
As feldon30 suggested, it is probably the particular variety that is being grown as well.
In some areas the dormancy period is brought on by low amounts of water (drought) rather than cold. I believe this is being used in some areas of Australia.
So I would suggest finding out what variety is being grown in Mexico and which method they are using to produce the dormant period or if they are using the "mother fern" method described in the New Zealand article.
Karen
I planted some unamed variety from Wal-Mart in San Diego and it's doing fine and seeding itself here and there. This is a sub-tropical climate with very little rainfall. I've also seen it growing wild here.
Thanks for the link to the article about the "mother fern" method. That may be what they are using here.
It still seems odd that people who write about asparagus, especially those who are selling the plants, don't mention that a period of dormancy will have the same effect as a chill period, if that is the case. I did see another article (can't remember where now) that suggested this.
katiebear
If it is seeding itself, you probably purchased a variety that produces both male and female plants. Mary Washington is a likely possibility. I think Jersey Knight and Jersey Giant are both all-male varieties. I did notice a comment that UC157 does well in tropical climates and under desert conditions.
I planted asparagus crowns a year ago. Because I had just planted them, I did not pick any spears last year. The spears that did come up I allowed to develop into ferns. The plants were dormant long before we had our first frost. So, at least in my garden, cold did not cause the dormancy. The cold may have kept them dormant, though, which is the idea with droughting as well.
I've been picking asparagus now for several weeks. I've started to have the problem that the spears shoot up so quickly that one day it's three inches high and two days later it's a foot and a half high and turning into a fern. So, I've been thinking about that "mother fern" idea. Maybe if I let the ones that get away from me turn into ferns I can still pick some spears through the summer, and the ferns will be building up food for the dormant period at the same time.
I did read a while back about picking only half the bed when it comes out of dormancy, letting the other half develop ferns, then at mid-summer switch to picking the half with the ferns and letting the first half develop ferns. This was suggested as a way to extend the picking season and still give the entire bed the ability to store nutrients for next
year. Sounds like a variation of the "mother fern" idea; doesn't it?
I assume that the info you've been seeing about zone limit on asparagus is old information that's being repeated without being updated. Sometimes the information is just plain wrong, too. I've got plants all over my yard coming out of dormancy that are supposed to be dead. No way some of these plants are supposed to survive the winter here, but they did.
However, your observation that the asparagus you planted is doing fine, even seeding into the wild, proves that you are right and there should be no reason you can't grow it. So, go for it, and let me know how it turns out.
Karen
I was told asparagus is a wierd vegetable that likes an alkiline soil which is rare in the south - luckily I have over 7 & planted today.
Luzianneagourmet,
Mine are planted in raised beds because of the red concrete that serves as "soil" here. I tested the beds for PH, and they are pretty close to neutral. Mine are growing just fine. This year will be their third year in the ground here.
I couldn't find anywhere on the Internet that agreed that asparagus like alkaline soil. The articles I found that mentioned PH at all said 6.5-7.0 and 6.5-7.5, which is neutral to slightly acid. I also found a comment that asparagus won't do well if the PH is less than 6.0, but that's getting into the acid range not alkaline.
It was mentioned that while they have to be watered frequently, the soil must have good drainage otherwise the roots will rot.
Karen
Yes, they really don't like below 6.5 & prefer neutral to more alkiline - need to be watered well first year or so, then don't need much irrigation after as they make roots up to 10' deep. Got info from Michigan St. U.......
http://www.asparagus.org/maab/homeGarden.html?id=771