japanese beetles life cycle control organic gardening

Japanese Beetles are an invasive insect that first arrived in the Midwestern United States in the 1990s and they are, unfortunately, likely here to stay. The larvae/grubs feed on plant roots and the adults skeletonize plant foliage. Damage usually becomes apparent in mid to late summer, when the adults are active and feeding above ground. They are easily identified by their metallic green color and their tendency to gather in large numbers on favored plants.

Due to their life cycle and their mobility as adults (adults can fly up to a mile), Japanese Beetles can be challenging to control. Damage to plants can be minimized, however, by utilizing a multi-pronged approach to control. The first and easiest way to discourage Japanese Beetles is to select plants for your landscape that they are not as likely to attack, and to avoid those that they prefer.

A partial list of plants that are resistant to Japanese Beetle damage follows:

Resistant Perennials

  • Yarrow (Achillea)
  • Ornamental Onion (Allium)
  • Butterfly Weed (Asclepias)
  • Aster (Aster)
  • Masterwort (Astrantia)
  • False Indigo (Baptisia)
  • Turtlehead (Chelone)
  • Coreopsis (Coreopsis)
  • Dianthus (Dianthus)
  • Bleeding Heart (Dicentra)
  • Ferns (Ferns)
  • Blanketflower (Gaillardia)
  • Prairie Smoke (Geum)
  • Baby’s Breath (Gypsophila)
  • English Ivy (Hedera)
  • Lenten & Christmas Rose (Helleborus)
  • Daylily (Hemerocallis)
  • Coralbells (Heuchera)
  • Hosta (Hosta)
  • Iris (Iris)
  • Gayfeather (Liatris) – pictured
  • Lilies (Lilium)
  • Beebalm (Monarda)
  • Catmint (Nepeta)
  • Spurge (Pachysandra)
  • Poppy (Papaver)
  • Obedient Plant (Physostegia)
  • Black-Eyed Susan (Rudbeckia)
  • Sedum (Sedum)
  • Toad Lily (Tricyrtis)
  • Veronica (Veronica)
japanese beetles control perennials organic gardening johnson's gardens cedarburg

Resistant Annuals

  • Ageratum
  • Snapdragons
  • Begonia
  • Cosmos
  • Impatiens
  • Ornamental Kale
  • Lantana – pictured
  • Nasturtium
  • Nicotiana
  • Ornamental Pepper
  • Pansy
  • Petunia
  • Portulaca
  • Verbena
japanese beetles control annuals organic gardening johnson's gardens cedarburg

Resistant Trees & Shrubs

  • Arborvitae (Thuja)
  • Boxwood (Buxus)
  • Burning bush (Euonymous)
  • Dogwood (Cornus)
  • Lilac (Syringa)
  • Forsythia (Forsythia)
  • Juniper (Juniperus)
  • Magnolia (Magnolia)
  • Pine (Pinus)
  • Red Oak (Quercus)
  • Redbud (Cercis) – pictured
  • Red Maple (Acer)
  • Spruce (Picea)
  • Tulip Tree (Liriodendron)
  • Yew (Taxus)
japanese beetles control trees organic gardening johnson's gardens cedarburg