Thank you for contacting Ask Extension with your question on how to deter rabbits and deer from your garden.

I know rabbits can be pesty and a few ways to keep them away from your plants is habitat modification, fencing, repellents, and scaring. Discouraging habitat and hiding places helps greatly. Keeping grass cut to a short length helps minimize their natural cover. Rabbits often hide in tall grass, this is also where they raise their young. Large brush piles and areas with tall weeds should also be minimized. A fence is another great option however, rabbits can dig. Burying the fence may be necessary to fully exclude them. Rabbit browsing can be discouraged by repellents. Unfortunately, repellents are not always effective and need to be reapplied regularly. There are also lists of plants that rabbits do not like. This is another option that works sometimes. If they are hungry enough, they will eat anything. The option of scaring with loud sounds and motion sensors will work for a while; but they will get used to these distractions and ignore after a while. More on these strategies: https://henderson.ces.ncsu.edu/2024/03/rabbits-in-the-landscape/

The same ideas apply for repelling deer. Deer black netting seems to be somewhat successful. University of Georgia research has shown that Milorganite (a fertilizer) can temporarily repel deer from food plots and ornamental plantings. However, Milorganite doesn't eliminate deer damage, and its effectiveness varies by location. There are other deer repellents available that are somewhat effective but they must be re-applied regularly. They may also stop being effective if the deer decides to ignore. There are numerous lists of deer resistant plants, but as noted for rabbits, they will eat anything if hungry. This is a link to one of these lists: https://extension.umd.edu/resource/deer-resistant-native-plants/

On monarch butterflies, the following link will take you to an article on Raising Monarch Butterflies and some of the programs in progress in Delaware: https://cast.desu.edu/sites/cast/files/document/16/7-22_raising_monarch_butterflies.pdf

I hope one of these methods of repelling deer and rabbits works for you.