The General Assembly is expected to consider a bill that would ban fertilizer containing phosphorous from being used on most lawns, golf courses, parks, and cemeteries in Virginia.

Phosphorus runoff from lawns is a major cause of a “dead zone” in the Chesapeake Bay, where it acts as a nutrient for algae that can overwhelm plants and some marine animals.

The bill, introduced last year and postponed till this session, would not apply to smaller areas — gardens, trees, shrubs, or indoor plants. But huge tracts of land would have to be fed using a phosphorous-free fertilizer. Stores would be required to have the phosphorus-free products on shelves, but could sell products containing the mineral upon request.

How common is phosphorous in plant food? Well, you know those three numbers you often see — e.g., 5-10-5? The middle number is the amount of phosphorous.

So instead of this:

fertilizer

You would need to use this:

fertilizer_0

Arlington already bans lawn fertilizer with phosphorus, and many states and localities limit or ban the use of laundry or dish detergents that contain it.