Appearance - Narrowleaf milkweed is a flowering perennial sending up many thin, erect stems and bearing distinctive long pointed leaves which are very narrow and often whorled about the stem, giving the plant its common name. It blooms in clusters of lavender or lavender-tinted white flowers. The fruits are smooth milkweed pods which split open to spill seeds along with plentiful silky hairs. This plant is common in the western United States and has the potential to become weedy. The plant is deciduous in winter and will die back to the ground before reviving in the spring, and is often covered with aphids, so often best to plant in less prominent spots in a garden. Note aphids can serve as ladybug or bird food.
Importance- Milkweeds are the larval host plants for Monarch butterflies, and this species is probably the single most important host plant for Monarch butterflies in California. Milkweed gardeners should be prepared for the plant to be eaten by Monarch caterpillars but will be rewarded by the presence of beautiful Monarch Butterflies.
Garden Plan – Milkweeds are commonly used in Butterfly and Bird Gardens. They are deer resistant. Narrowleaf Milkweed works well with a wide variety of other plants but is best used where its winter leaf loss and summer consumption by caterpillars will not be the center of attention. Also, plant several Milkweeds in proximity so that caterpillars will have enough to eat. Use with showy, nectar-rich plants that will attract adult Monarchs, such as Indian Mallow (Abutilon palmeri), Ceanothus sp., Fuchsia (Epilobium sp.), Buckwheat (Eriogonum sp.), Mint (Monardella sp.), Monkeyflower (Mimulus sp.), Penstemon sp., Sages (Salvia sp.), Apricot Mallow (Sphaeralcea ambigua).
Planting Directions – Narrowleaf Milkweed has been very successful in full sun to filtered shade in Porterville. Calscape lists that it can be grown in a variety of soil types including clay. Mark the location of your Milkweed plants with rocks or sticks so that you will know where they were planted. Water your new plants twice a week until the weather is cool. After the first hard frost do not overwater. They will resprout in the late spring and grow slowly the first year. During the first year they are growing a root system. The following years you will see more rapid growth, taller plants and possibly flowers and seed pods. Milkweed spreads from underground runners and seed. You can limit this by creating an underground barrier or just pulling up sprouts. Milkweed will grow well with once every other week summer watering once established. Consider the needs of the adult Monarch and plant a variety of flowers near the milkweed to provide nectar to the butterfly. Narrowleaf Milkweed flowers are beautiful, but the plant has narrow stems with narrow leaves. Its best suited to planting in clusters with other pollinator plants taking center stage. Milkweed can be grown in patio pots, since dies back to the ground in the winter, consider planting with an evergreen plant in the same pot to provide winter beauty.
Warning - It is crucial to not use any pesticide on this plant or in its vicinity because doing so will be fatal to Monarch caterpillars.