Answer: If critters are eating your plantings, it may be that there is an overpopulation problem or that there are too few native plant food sources for the critters. It may also be that they just prefer your plants -- in so many cases critters will adapt and learn to eat introduced plants quickly, especially if the plants are easily available to them! When you look at the overall pictue you may find that a certain amount of critter damage is acceptable given the altrnative control measures. You might even find it welcome if your plants are filling an unmet need for an unusual or endangered bird or animal.
If you are trying to plant a purely ornamental garden, you may have to fence it off to ensure there is no critter damage. In my experience that is the most reliable prevention and may be the only viable choice if you are embarking on extensive plantings of any kind -- especially if there are deer in the area.
If you are trying to establish a more naturalistic planting that will sustain itself over time then your choices will be limited to those plants that are ideally suited the local growing conditions so that they can survive on their own once they are established. Often you will find that native plants meet these criteria very well and can be highly ornamental when used carefully as well as easy to maintain when naturalized or reintroduced to an area. You may also find that you need to eradicate a number of excaped invasive exotic plants (such as honeysuckle vines) in order to allow the native plants to thrive. When planting, even if you do not use exclusively native plants, do be aware of the risk of introducing invasives.
This is a complex project and to make good choices you will need to do some careful site evaluation so that you know specifically what types of conditions exist. You might want to consult with a variety of public and private sources for localized information and assistance not only about the plants but with naturalists too. Some places to start would be with local wildflower specialists such as Garden in the Woods in Framingham and with your local UMAss Extension office. All the best with your project!
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