Most home depots should carry some powdered iron products. However such products don't work for long. A longer term solution is to topdress the lawn with a screened compost about 1/3 inch deep and then aerate as deeply as you can. The iron supplements are fine but you also need to look for a more long term fix. Be careful not to get iron on sidewalks and other masonry as it will stain it a rust color.
Thanks for the question. Please stop in again soon!
Q&A Library Searching Tips