En Español

Q. Who is Mr. Smarty Plants?

A: There are those who suspect Wildflower Center volunteers are the culpable and capable culprits. Yet, others think staff members play some, albeit small, role. You can torture us with your plant questions, but we will never reveal the Green Guru's secret identity.

Help us grow by giving to the Plant Database Fund or by becoming a member

Did you know you can access the Native Plant Information Network with your web-enabled smartphone?


Ask Mr. Smarty Plants

Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

Search Smarty Plants
See a list of all Smarty Plants questions

Please forgive us, but Mr. Smarty Plants has been overwhelmed by a flood of mail and must take a break for awhile to catch up. We hope to be accepting new questions again soon. Thank you!

Need help with plant identification, visit the plant identification page.

rate this answer
3 ratings

Monday - November 02, 2009

From: Burnet, TX
Region: Southwest
Topic: Butterfly Gardens
Title: Propagating milkweeds for a monarch butterfly habitat
Answered by: Nan Hampton and Sean Watson


I am planting a monarch habitat in Burnet, Tx with Antelope horns, Green milkweed, and butterfly weed. Should I plant in fall or spring??? Should I use cold moist stratification for 3 months at 40 degrees in sand on all three types of milkweed or just antelope horns. Is is better to plant in peat pots or clay pots over the winter and then transplant in spring around March???


Mr. Smarty Plants assumes that the following are the milkweeds you want to grow in your monarch habitat:

Asclepias asperula (antelope horns), Asclepias viridis (green antelopehorn), Asclepias viridiflora (green comet milkweed) and Asclepias tuberosa (butterfly milkweed)

To learn the best method for propagting these, Mr. Smarty Plants consulted Sean Watson, the Wildflower Center nursery manager who offered this advice for you:

I have never had trouble with milkweeds germinating (no stratification needed). If you use the freshest seed possible, sow them in a tall pot or seed flat with deep cells to start them (room for taproots), and keep them moist until you see the first pair of true leaves, you should have great success. You could then transplant them into a larger clay pot to overwinter (clay pots would be best since they breathe) and then transplant them into the ground in the Spring. It would be best to cover the flat/pot with a clear plastic container to act as a greenhouse if you want to start them now. After transplanting them into the clay pot and/or ground, water in thoroughly and then allow to dry out slightly between watering from that point until established (they like to rot once the taproot begins to get larger/fleshy since at this point the roots hold more water so the plant needs less). Just make sure the final site is well drained.

You would have much better success, however, if you wait until February to start them so you can transplant them out in early spring (that way the root system is able to develop more before the next winter). In either case, making a mini greenhouse will allow for greater germination percentage because of increased humidity (I use an aquarium at home). The most important thing seems to be giving the taproots room to grow. ALL milkweeds I have ever grown have always grown much better in the taller gallon pots/or tall tree pots than the shorter, square 4-inch pots. They seem to grow much better when started in early to mid spring (i.e. they love heat).

Asclepias asperula

Asclepias viridis

Asclepias viridiflora

Asclepias tuberosa




More Butterfly Gardens Questions

Hedge shrubs that attract butterflies & birds in Virginia
June 13, 2014 - Hi - I need recommendations for north VA hedge shrubs that attract butterflies and birds. Thanks
view the full question and answer

Butterfly plants for Washington DC area
June 28, 2009 - Dear Mr. Smarty Plants, I am a teacher working with very young students to establish a wildlife garden. We received a donated butterfly bush of a smallish cultivar, but wondering if there is a native...
view the full question and answer

Fall seeding of Butterfly Weed in Virginia
July 20, 2007 - Just ordered seeds from you - Butterfly Weed - and I plan to hopefully scatter the seeds early Oct. in an area along a tree line here in No. VA where the sun bakes the soil as it is exposed to hot wes...
view the full question and answer

Non-toxic plants for dog yard from Freeport PA
June 24, 2012 - I'm looking for wildlife-friendly native plants that aren't toxic to dogs. I have a place for some small shrubs and/or flowers. And a climbing vine that I could train on a trellis would work espec...
view the full question and answer

How toxic are milkweed (Asclepias spp.)?
November 01, 2011 - We are considering a monarch waystation for our local elementary and are concerned about milkweed toxicity. Would it be safe to plant it in reach of children?
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
© 2016 Lady Bird Johnson Wildflower Center