Hi, 

These look like harlequin bugs but the photo is a little blurry to see clearly enough. You can follow the link to see management techniques. At this point a floating row cover won't help since they would just get trapped inside but you can hand pick them off or look for the egg masses and scrape or squash them. 

You can also try some insecticidal soap just read labels and make sure it is for edibles and follow application directions. Insecticidal soap kills on contact so you want to direct it towards the insects and make sure you get under the leaves as well. Be careful not to burn the foliage by applying it if the heat is too high. 

Let us know if you have further questions. 

Emily