Although it is certainly possible to freeze asparagus without blanching it first, it is highly recommended that you avoid doing so because of the fact that the taste will be quite dull when you take it out to thaw. There are a variety of ways which you will be able to freeze this vegetable, including putting the spears in boilable bags.
This is by far the fastest method of freezing asparagus. First you will need to start by cleaning off the spears by washing them thoroughly. Place however much you want to freeze in these special bags, add all of the seasonings that you want, and press out all of the air from the bags before sealing them shut. Cool down the bags of asparagus in ice water, pat them until dry and freeze.
You will also be able to use tray packs with drained asparagus. All you will have to do is lay all of them flat on a baking sheet and put them in the freezer. This is one of the easiest methods of freezing asparagus and they tend to separate very easily when being cooked. It will be important to consider that blanching your asparagus before freezing it can add a little bit more taste and preserve it until you are ready to use it.