2 Types of Milkweed You Can Plant in Oregon (AND One to Avoid!)

“What types of milkweed should I plant in my garden?”

Common Milkweed in Oregon

This may seem like a crazy question if you’re just getting started with native gardening. Why would you want to plant a weed?!

 

But milkweed isn’t a weed at all. Instead, it’s a flowering plant that attracts butterflies (think Monarchs), native bees, and other pollinating insects, which is an excellent thing!

 

This article will give you information about common types of milkweed in your area and which ones will be best for your garden. And, keep reading to the end to learn about a kind of milkweed you want to avoid!

 

You will notice a USDA Hardiness Zone for each Milkweed plant in the article. This refers to areas of the US where plants do best, based on temperature. Here is a map showing the hardiness zones of Oregon:

Hardiness Zones in Oregon range from 4b to 9b.

 

2 Types of Milkweed in Oregon:

 


#1. Showy Milkweed

  • Asclepias speciosa

Types of Milkweed found in Oregon

Buy Seeds HERE!

Growing Information:

  • USDA Hardiness Zone: 3-8
  • Life Cycle: Perennial
  • Approximate Mature Size: 1.5 to 3 feet; occasionally up to 6 feet
  • Bloom Time: May to September

 

As the name suggests, Showy Milkweed features flashy pink and white umbels or clusters of small flowers. The flowers are fragrant, and individual flowers look a bit like crowns. In ideal conditions, Showy Milkweed may grow as tall as 6 feet!

Milkweed species that live in Oregon

As a garden plant, Showy Milkweed has the benefit of being a less aggressive spreader than most other milkweed varieties in Oregon. It can be grown easily from seed or the cuttings of an existing plant. It’s very drought tolerant and can be grown in a wide range of soils.

 

Like other milkweeds, Showy Milkweed attracts native insects and Monarch Butterflies to your yard or garden. Monarchs will visit the flowers for nectar and lay eggs on the plants, which are host plants for the Monarch caterpillars. It will also attract beautiful Queen and Viceroy butterflies to your property!

 


#2. Narrowleaf Milkweed

  • Asclepias fascicularis

Common Milkweed species in Oregon

Growing Information:

  • USDA Hardiness Zone: 6-10
  • Life Cycle: Perennial
  • Approximate Mature Size: 1 to 3 feet
  • Bloom Time: June to September

 

Narrowleaf Milkweed, sometimes called Mexican Whorled Milkweed in Oregon, is often seen growing in large groups. It has a much more delicate, grass-like appearance than Common Milkweed.

 

It’s most conspicuous when it’s in bloom, from June through September. The blooms are upright clusters of about 20 small flowers. The flowers are variable in color, from greenish to pink, white, and even purple. The thin, spiky leaves are arranged in a spiral around the stem. Beginning in July, seed pods replace the blooms. The seed pods are narrow, thin, smooth, and long. They split down the side and release wind-borne light brown seeds and coma when mature.

 

In the wild, Narrowleaf Milkweed is typically found in the dry climates of plains, foothills, valleys, and roadsides. In the garden, it can be started from seed and is a great low-maintenance plant. It thrives in areas with full sun and is drought-tolerant.

 

This species is a host plant for the caterpillars of Monarch and Queen Butterflies and Isabella Tiger, Clio Tiger, Hitched Arches, and Euchaetes Zella moths Various other pollinators like bumblebees and wasps also visit the plant’s blooms.

 


Tropical Milkweed

  • Asclepias curassavica

Growing Information:

  • USDA Hardiness Zone: 8-11
  • Life Cycle: Perennial
  • Approximate Mature Size: 3 to 4 feet
  • Bloom Time: March to November in temperate climates, year-round in tropical climates.

 

This non-native milkweed plant has become popular in recent years because of its flowers’ bright red coloring and how easy it is to plant and maintain.

 

Unfortunately, Tropical Milkweed planted in Oregon may do more harm than good.

 

It carries a parasite of Monarch Butterflies called Ophryocystis elektroscirrha, or OE, which can cause defects in the wings of Monarchs. Since it doesn’t die back and can bloom late, the plant itself may also confuse Monarchs by signaling a breeding season when it’s time to migrate.

To ensure you’re planting milkweed that will help your local ecosystem and attract native pollinators, always choose a native species!

 

Marketers of Tropical Milkweed seeds will use the names Mexican Milkweed, Bloodflower, Mexican Butterfly Weed, Mexican Orange Milkweed, and Semi-Tropical Milkweed. Steer clear of all of these!

 


Are you looking for more information on milkweed in Oregon?

 

Check out this guide!

 


Do you have milkweed in your garden?

 

What’s your favorite thing about this plant? Leave a comment below!

 

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