Natural deer repellent
Unfortunately, we cannot recommend a specific repellent. If you have deer in the area, you may need to use a combination of techniques. Hostas are a favorite food plant. Deer will eat anything if hungry enough. Keep in mind that deer may browse on any new plantings even resistant plants until mature. So you may want to initially protect them with repellents, deer netting/fencing, and planting resistant plants.
If you have to rely on repellents, they will have to be reapplied as they wear away in the elements. It also helps to rotate the repellents as deer can get used to them. Follow all label directions. Here is our publication on repellents
Here is more deer information on our website http://extension.umd.edu/hgic/deer