Asparagus in a Greenhouse?

Hi! I’m Mark.

I have a question for all you experts out there.

I have a heated Greenhouse, and I was wondering:

If I plant asparagus in a deep 3’x2’ tote with proper drainage holes in it, and keep the temperatures between 50’f and 80’f all year round; will I get continual harvests of asparagus throughout the year, or will they just flush one time in the spring?

Do they need to go dormant in order to produce like many fruit trees, or will they just keep on pumping out shoots???

Let me know what you think ASAP!!!

: )

Thanks in advance!

=M=

The annual cycle of asparagus is about a month and a half of spears that are large enough to pick, and then 10+ months of it just growing or going dormant.  When the spears get small and spindly, you need to let the plant just do it's thing.  It becomes a big, tangled mess -- ferny branches going all over the place.  It's not a space-efficient plant, but rather, it consumes a lot of garden space as the asparagus fronds flop over and try to maximize exposure to the sun so it can create an energy reserve for next season.  So if you had a place to transport those planting boxes/barrels/containers for the majority of the year when the plant isn't bearing, yeah, a greenhouse might be a solution.  But don't count on picking a big bunch of asparagus and having a nice amount for a meal.  You'll get 2 spears today, none tomorrow, 1 spear the next day . . .  There are so many more efficient veggies to grow in a greenhouse than big, tangly asparagus plants.  For the small amount of asparagus you'll actually get for all your effort, I'd spend $5 at Costco and buy a bunch there.

Hi, Mark!

Mark Seasigh wrote:
I have a heated Greenhouse, and I was wondering:
If I plant asparagus in a deep 3’x2’ tote with proper drainage holes in it [...]

I'd first point out asparagus roots go *deep*. Some say as deep as 10ft, but I'd definitely assume at least 6 or 7ft. I don't know how they'd behave if you restricted their root depth.
This is the reason why you don't really need to water them.

Second, I'd question why waste precious greenhouse space? Asparagus is hardy from zones 3 to 8. That's a fairly broad range. They do fine in my -10°F winters and 105°F summers (zones 6A). What I like about asparagus is it's a perennial that doesn't have to be pampered and don't really need watering (because of their root depth).

will I get continual harvests of asparagus throughout the year, or will they just flush one time in the spring?

Just in spring - for about 5 weeks or so. As the spears come up and you harvest them, the spears will get thinner and thinner as you use up the asparagus' reserved energy. When they get thinner than a pencil, stop harvesting it, so it can branch out and absorb sunlight and store energy in its roots for next year.

I have *heard*, but have yet to try, that if you let your asparagus branch out without harvesting any, then cut everything down after summer, they'll send up new spears you can harvest as a fall harvest.

*If* this is true (which I don't know for sure), a setup I'd like to try in a year or so would look like this:

Four beds of asparagus:
- Spring: Cover one in a coldframe, so it breaks dormancy sooner. Harvest over 5 weeks.
- Spring: Harvest the second bed when it breaks dormancy normally. Harvest over 5 weeks.
- Early Fall: Cut the branches on the third bed, and harvest over the next 5 weeks.
- Late Fall: Cut the branches on the fourth bed, and harvest over the next 5 weeks (requiring a frost blanket if the night drops to 32°F).

Thanks for the replies.

Well, now I’ll plant most of my crowns outside... and one in a tote in the greenhouse as an experiment...

I bought 10 medium crowns of asparabest variety today.

So, I’ll plant nine in a row, and one in a tote.

I’ll let you guys know how it goes in a month or two.

Thanks again for the replies.

=M=

My speculation is that after several years, the one in the tote will need watering, the ones in the ground won't, and the one in the tote will, due to limitation on root depth, not be able to produce as many consecutive harvesting of spears. I think it'll work but be less productive and need more watering.

I'd be very interested to hear how your experiment goes!

Marco Banks wrote:The annual cycle of asparagus is about a month and a half of spears that are large enough to pick, and then 10+ months of it just growing or going dormant.  When the spears get small and spindly, you need to let the plant just do it's thing.  It becomes a big, tangled mess -- ferny branches going all over the place.  It's not a space-efficient plant, but rather, it consumes a lot of garden space as the asparagus fronds flop over and try to maximize exposure to the sun so it can create an energy reserve for next season.  So if you had a place to transport those planting boxes/barrels/containers for the majority of the year when the plant isn't bearing, yeah, a greenhouse might be a solution.  But don't count on picking a big bunch of asparagus and having a nice amount for a meal.  You'll get 2 spears today, none tomorrow, 1 spear the next day . . .  There are so many more efficient veggies to grow in a greenhouse than big, tangly asparagus plants.  For the small amount of asparagus you'll actually get for all your effort, I'd spend $5 at Costco and buy a bunch there.

What plants would you suggest to grow year round in a greenhouse?
So far I’ve decided on Everbearing/day neutral strawberries and a couple different kinds of tomatoes.

=M=

Jamin Grey wrote:My speculation is that after several years, the one in the tote will need watering, the ones in the ground won't, and the one in the tote will, due to limitation on root depth, not be able to produce as many consecutive harvesting of spears. I think it'll work but be less productive and need more watering.

I'd be very interested to hear how your experiment goes!

I’ll post some pictures in a couple months/weeks.

: )

It’s an Experiment!!! Hehehe!!!

=M=