Yes, after a couple weeks, we recommend that you fill the holes with soil and grass seed. This way, it is easier to tell if any new voles or other rodents are trying to get into the same areas. If holes are created again, wait 2 more weeks and fill the holes again. That should be enough time for the voles to be exterminated and your vole problem solved. If you notice a persistent issue, do not hesitate to call us for a free service call and we will check the matter quickly. With our program, you can be confident that you will get the best customer service experience.