I can’t speak from experience, but if you know your grass is immaculate, clean of chemicals, urine from animals, and bug eggs, than I don’t see why not. But do consider the following:
Many rabbits won’t really go bonkers for hay when they know veggies (or greens, if that’s what you mean by greens) are an option, so I’d first try and increase hay appetite by adjusting veggie feeding to once a day (maybe in the morning, and no other time), and also by trying another type of hay. Lots of rabbits love Orchard Hay, because it’s leafy and more soft than timothy. Some rabbits also enjoy Oat Hay as well! Another important aspect is the freshness of the hay. When it’s hay that has been sitting in Burfee’s space for a day, it may smell less appealing, so you can take any uneaten & unsoiled hay, toss it with new hay, then replace it in Burfee’s eating spots. This may help too!
The answers provided in this discussion are for general guideline purposes only. The information is not intended to diagnose or treat your pet. Seek the advice of your veterinarian or a qualified behaviorist.