Timing challenge: Best way to preserve tomatillos prior to making canned salsa verde?

So thats it- my tomatillos are coming up now but my chillies are not ready yet. My idea was to pick them gradually and freeze and then later on thaw it to make canned salsa verde to use all year round.

Wonder if anyone tried this before.

- did you roast them and freeze them whole?
- did you roast and make puree and freeze the puree?
- do you prefer blanching and freezing whole or puree?

Also: if you have any canned salsa verde recipes you recommend it is more than welcome.