Few things frustrate gardeners more than watching meticulous planning and hard work destroyed by foraging wildlife within chewing distance. As fall planting season arrives, selecting the proper varieties can prevent your garden beds from becoming a dinner menu for local animals.While no plant offers absolute immunity from hungry creatures, several spring-blooming bulbs possess natural chemical self-defenses, unpalatable tastes, or toxic properties that deer, rabbits, and rodents tend to avoid. However, because these protective mechanisms can pose risks, parents and pet owners should exercise caution when planting them within reach of children or pets.Critter-resistant daffodils in bloom on Long Island, N.Y. (Jessica Damiano via AP)Among the most potent deterrers are crown imperials, commonly nicknamed "stink lilies." Their downward-facing, tufted, bell-shaped flowers release an intense odor resembling a skunk or a sweaty locker room, while the plant itself contains highly toxic steroidal alkaloids. Despite the strong odor, they make striking additions to spring gardens, repelling rodents while attracting pollinators—though planting them directly beside front walkways is discouraged.Alliums, which are related to onions, carry an unmistakable aroma in their bulbs and a milder fragrance in their blossoms. If rabbits attempt a nibble, bitter sulfur compounds in the bulbs, leaves, and stems will send them running, and the plants are toxic as well. Similarly, daffodils of every variety—from demure jonquils to giant trumpet types—contain bitter, poisonous properties that most animals naturally avoid.Other bulbs rely on scents or tastes that are off-putting rather than outright repulsive. Dutch hyacinths produce a strong, sweet perfume enjoyed by humans that deters animals, whereas the fruity scent of unrelated grape hyacinths is perceived as musky by deer and rabbits. While less pungent than alliums, both hyacinth types feature toxic compounds that cause mouth irritation and stomach upset if bitten or ingested. Meanwhile, Spanish bluebells contain soapy-tasting saponins along with poisonous cardiac glycosides.If you’re planting bulbs this fall, select the right ones to avoid planting dinner (Jessica Damiano via AP)Smaller options—frequently referred to as "minor" bulbs because they flower earlier than larger varieties—also pack a punch against wildlife browsing. Plants such as snowdrops, Siberian squill, anemone, glory of the snow, winter aconite, and star of Bethlehem deter animals with unpalatable smells, bitter tastes, or toxic compounds. However, because animals leave them alone and they multiply easily, species like Siberian squill, Spanish bluebells, and star of Bethlehem can quickly become invasive if planted without caution.Gardeners can take advantage of these natural defenses to protect varieties that animals love to eat, such as tulips and crocuses. Surrounding susceptible plants with unpalatable ones allows the protective chemicals and scents exuded into the soil and air to extend defense to neighboring bedmates.