Native Plants
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.
Did you know you can access the Native Plant Information Network with your web-enabled smartphone?
Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.
rate this answer
Tuesday - May 29, 2012
From: Alton, VA
Region: Mid-Atlantic
Topic: General Botany, Poisonous Plants
Title: Can foxglove poison be transmitted to the soil and taken up by another plant
Answered by: Nan Hampton
QUESTION:
Hi Mr. Smarty Plants, Recently I discovered a Foxglove that had come up after being planted 2 or 3 yrs ago. Next to it I have some medicinal Feverfew growing. (They were so close together I suspect they were sharing root space.) Is it possible for the Foxglove to have passed its poisons on my Feverfew? If there is a remote possibility I will pull up the Feverfew, to ensure our safety. Thanks for your time in answering.ANSWER:
Mr. Smarty Plants assumes you mean Digitalis purpurea (purple foxglove), a native of Europe, which is highly toxic. However, if you mean Penstemon cobaea (Wild foxglove) or Penstemon digitalis (Foxglove beardtongue), they are not on any toxic plant list that I have checked. There are several species of Agalinis that are called "false foxglove" and none of these appears on any of the toxic plant databases either. Any Penstemon or the Agalinis would be fine growing with your feverfew.
There are plants that produce chemicals that can affect other plants, either beneficially or harmfully. This is called allelopathy and, generally, the effect is associated with competition between plants and inhibiting the growth of other plants. The allelopathic chemicals may affect the target plant by leaching into the soil from fallen leaves or fruit or they may be exuded by the plants' roots. The classic example is the allelopathic effect of walnuts which were known as early as Roman times to kill or otherwise inhibit the growth of other plants near them. Not all plants release chemicals into the soil and I could find no evidence that Digitalis purpurea does. Plants certainly take up mineral and chemical compounds from the soil where they grow and are known to take up toxic substances such as lead, arsenic and mercury. However, I can't really find evidence that a plant such as Digitalis purpurea exudes any of its toxins into the soil and, if it does, that Tanacetum parthenium (Feverfew) would be capable of taking up enough of the toxin to be harmful. You might feel safer about using the feverfew, however, if you moved it to another spot in your garden and leave the purple foxglove growing where it is.
More Poisonous Plants Questions
Is Echinacea poisonous to cats?
May 01, 2008 - Is the echinacea plant poisonous to cats?
view the full question and answer
Herbal properties of Dicentra formosa
January 23, 2016 - I would like to get some information on the Dicentra formosa plant such as the benefits of the plant. Is it poisonous? Can it be infused in an oil?
view the full question and answer
Is Bignonia capreolata (Crossvine) known to cause skin irritation
July 23, 2013 - Is Crossvine (Bignonia capreolata L.) known to cause a rash? We are trying to identify the source of a rash-after-gardening, and have not seen any of the big three (poison ivy, poison oak, poison suma...
view the full question and answer
Effects of Hedysarum mackenzii from Pflugerville TX
May 08, 2013 - What are the effects of Hedysarum mackenzii?
view the full question and answer
Evergreen trees for California that are non-toxic for dogs
February 19, 2014 - Hi,
we live in California, San Bernardino County and would like to know what evergreen trees are safe to plant in our backyard with 2 little dogs being around. I did quite some search online but ever...
view the full question and answer
Support the Wildflower Center by Donating Online or Becoming a Member today. |