Saturday, August 21, 2010

Velvetleaf Milkweed - Asclepias tomentosa

Velvetleaf milkweed (Asclepias tomentosa) is a rather nondescript member of the milkweed family which occurs in a variety of well-drained upland sites throughout most of Florida and the Southeast.  This is a deciduous species and dies back to the ground in the late fall after its seeds are released.  As it emerges in the spring, it can go largely unnoticed as it sends its stalk upwards.  Eventually, it reaches a height of about 3 feet in summer.  The individual stalks are stiff, and opposite rounded leaves occur along the length of each.  The leaves are somewhat fuzzy in texture; hence the common name.
Blooming occurs in summer.  The flower buds are arranged in a conical head at the top of the stem and the plants remain in flower for several weeks.  The flowers are a rather greenish white and not very showy, but they attract the same types of pollinating butterflies as any other milkweed.  Pollinated flowers eventually produce large elongated pods.

Velvetleaf milkweed has never been offered for sale commercially by anyone associated with AFNN- the Association of Florida Native Nurseries, and it is not an easy species to keep in the home landscape.  I have found it to be very sensitive to having the proper drainage and will quickly rot if not given well-drained sandy soils and good levels of sunlight.  It is, however, a good candidate for gardeners looking to use native milkweeds in a butterfly garden.  Because of its size, it can handle a good number of caterpillars before being completely defoliated - something which is not true of many of our more-diminutive native milkweeds.  The leaves produce an abundance of milky sap as well - a trait necessary in protecting caterpillars from predation by birds.
Perhaps someday, someone will begin propagating this species for that segment of earnest butterfly gardeners who would value the plant more for its value than its aesthetics.  But, until then, anyone with an interest will have to be lucky enough to find a few seeds at the right time and place.  I have not grown velvetleaf milkweed for more than a decade and we are unlikely to attempt it again at Hawthorn Hill unless we get some demand.  Let us know and we'll keep our eyes out.

7 comments:

  1. I am interested in growing Velvetleaf milkweed for the size of the leaves as a host to hungry caterpillars. annie.grewe@gmail.com

    ReplyDelete
  2. I too would like to get a hold of some seed for my yard. if ever available. I am actually also looking for Asclepias Humistrata seed or plants. I live in central florida. Do you have any?

    It would also be great to see Lowes (and other commercial companies) selling the tropical milkweed educated about how they are contributing to the demise of the Monarch. :/ If they were educated more nurseries would be more financially motivated to grow native milkweed knowing there is a market for it. i digress... Thank you Tamara

    ReplyDelete
    Replies
    1. I agree that it would be wonderful if native FL milkweeds were more widely available, and there is a FL Milkweed Project seeking to more in that direction, however, many of the upland species such as A. tomentosa and A. humistrata are nearly impossible to grow in a container (they die at very small sizes) and I can't foresee a time when they would be made available in any quantity - especially by a "big box store". I have tried a good many upland milkweeds and had very dismal success with them.

      Delete
  3. What growing medium did you have them in and what size pot when they died? I'm interested in this species as well

    ReplyDelete
    Replies
    1. I have tried growing this, and other sandhill plants, in regular potting soil mixed with perlite to increase the soil porosity. This and A. humistrata, are very difficult to keep in pots for any length of time - or to be moved from pots to the ground. I would recommend using a small, but deep pot and transferring them to the growing site while they are small - with minimum root disturbance as possible - maybe using a deep, very thin-walled peat pot - not the sturdy kind. If you have success, let me know.

      Delete
    2. I have tried growing this, and other sandhill plants, in regular potting soil mixed with perlite to increase the soil porosity. This and A. humistrata, are very difficult to keep in pots for any length of time - or to be moved from pots to the ground. I would recommend using a small, but deep pot and transferring them to the growing site while they are small - with minimum root disturbance as possible - maybe using a deep, very thin-walled peat pot - not the sturdy kind. If you have success, let me know.

      Delete
  4. I have taken to stratification/scarification of the seeds and will be sowing directly into the ground with both a.tuberosa and a. Humistrata due to the taproot. I managed to find seeds for both. As far as lowes and other box stores goes education of customers is key. I also think people, myself included, have become way to accustomed to buying greenhouse grown plants in pots. It's a very bad habit.

    ReplyDelete

Please let me know if this site and the various postings have been useful to you.