"Mary McHugh" ...
JRYezierski wrote:
How old is the bed?

About 7-8 years.
All right .You should be able to pick till the end of June if you are in
zone 5.As about that time its getting very hot and they are growing like
crazy that you could harvest in the morning and again in the evening (which
you do not want to do if you want the bed to last you another 15 years.
How long have your been harvesting them this year?

Just started so maybe 1-2 weeks. I usually follow the advice to harvest
until the spears become as thin as pencils. Then I let them fern out.
I still have plenty of thick spears coming up.
You are missing some tasty stuff if you are not picking the thins ones
now and eating them.Penicl thin are great #2 bunches that sell like crazy
around here.We always cut dowen the thinner than pencil ones while we were
harvesting as it gives the roots a rest. If you harvest until it gets too
hot or all that you are getting are "skinnys" than stop for the season.
Since your bed is young you should get another 15years out of.Unless evan at
the begging of the season all you have a "skinnys" than its time to replant.
How tall are they when your harvest them?

I usually harvest around 6-8".
And if you cut them about 2inchs below ground you are doing excellent.
The snapping them off some folks do really isn't that good for the roots
as often it will keep growing or bleed/seep which weakens the root,as when
cut under ground it gets an instant band-aid.
When harvesting you should be cutting down all the spears that are
thinner than a pencil just leaving the ones that are too small to pick
today.You should also be picking all the "crooks"(ones that are bent over
due to a windy day) as they are just a tasty.
We grew for the Boston veggie market for years and all we ever ate were
the rejects,crooks,skinnys whcih most of the time was just the tips when we
finished bunching the days harvest up.
A good asparagus bed should last you 20 to 35 years when taken care of.
Hope this helps you out.
Jerome