Perhaps, more spanish language on labels would be good, but current policy and regulations do not require much in the way of languages other than English. All labels sold in this country must be in English. That's the minimum standard. Hope that helps at least a little bit. I checked with EPA HQ some time ago on this issue, and was told that there are NO accepted labels in Spanish.
Spanish labels marketed in other countries are almost certainly different from the U.S. products.
If these growers are to be applicators, they must be able to read and understand the label or they must have it explained to them in a language they understand. You should find that much in Spanish on the label. In general, employees need to be given pesticide safety information in a language they can understand. Owners have the responsibility to comply with all applicable laws and regulations regardless of their ability to understand English. In California, where we have many more Spanish-speaking growers and applicators, there is a test given in English.