What do you feed your asparagus and how often?

I have been using the fertilizer I received from Gurney's. I have only feed them twice since i have been gathering spears. They are starting to develop the ferns now. We had a month's worth of vegetables. About 6 meals for the 3 of us. Should I have feed them more? Also is compost, grass clippings and chopped leaves sufficient after this fertilizer is gone?
Should I feed it now that they are going to seed?

They are 2 years old.
Thanks, Linda

Hard to say if you should've gotten more spears or not, you didn't say how many crowns/plants you have growing.

However, you could give them a light feeding now but I'd let that be the last one for the year.

Next Spring (or late Winter) just throw some finished compost or manure on the bed; that should be all the food they need for the year.

Shoe.