Good morning and thank you for your question.  While it is early in the season and there likely aren't many beetles, I would encourage you to hand pick them and toss them in a bucket of soapy water.  Hopefully, you're also seeing wasps and lady beetles in your garden that will also help to manage these pests. Pesticides should be avoided if possible as they will also kill any natural enemies that are present.  When pesticides are used, always read the pesticide label and wear appropriate PPE.  Here is a factsheet for your reference:  https://vegento.russell.wisc.edu/pests/asparagus-beetle/

Happy Gardening, 
Jen