Butterfly Milkweed (Asclepias Tuberosa). This North American native has clusters of orange-red flowers that attract variety of butterflies, including the treasured Monarch. A perennial (to zone 4) growing 18 to 36" tall, it requires well-drained soil and prefers full sun. The wind will carry the fluffy seeds great distances. Wintersow in a cold frame, or cold moist stratify for 4 weeks in moistened sand, then germinate warm.
|How To Grow||Sow seed indoors in a soil-less mix in early March for late summer flowering in the first year. Growing medium temperature should be about 20 C (68 F). After germination, grow-on under lights at a cooler temperature of 15 C (60 F) before hardening off and planting out to a sunny site after the danger of frost has passed. Dormant fall seeding in mid October is also a good way to start not only this plant but many other perennials. Dormant seeding allows any dormant seed to be naturally stratified over the winter.|
|Blooming Season Begins||High Summer|
|Propagation||Start Indoors or Sow Direct in Fall|
|Days to Emergence||10 to 20|
|Height||Medium (50 to 70 cm)(20" to 28")|
|Frost Tolerance||Winter Hardy|
|Degree of Difficulty||Easy|
|Heritage||Native of Canada|
|Suggested uses.||An absolute must have plant for any butterfly or pollinator garden.
Superb performance in droughty, sunny sites
Regularly used in native meadow mixes.
Eye catching colour!
|Requires Stratification||For the seed from many native plants, late fall is the best time to sow seed directly outside. Why you ask? Simply put, many native plants produce seed that is viable but dormant. This means that while the seed has all the internal structures and nutrients required to germinate, the seed coat is so hard, water cannot pass through it and initiate germination. When seed is in this state, it is known as being dormant. Seed dormancy is a naturally selected for trait that protects the seed of many plants allowing them to safely overwinter and then be ready to sprout in more favourable conditions in spring.
The remedy to naturally breaking seed dormancy is typically the passing of time. In particular, seed overwintering outside and experiencing the natural freeze thaw cycles that occur in late fall, winter and early spring. This dormancy breaking process is called stratification.