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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.

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Friday - June 15, 2012

From: King, NC
Region: Southeast
Topic: General Botany, Poisonous Plants
Title: What is white sticky substance in the Mandevilla vine?
Answered by: Nan Hampton

QUESTION:

When I was watering my Mandevilla one of the vines broke and there was a white, sticky substance that came out of the vine. I was just curious as to what that is.

ANSWER:

The white sticky substance is the sap of the Mandevilla.   Mandevilla species, native to South America, are members of the Family Apocynaceae.  The majority of the members of the family have this thick milky sap sometimes called latex.  Mandevilla spp. are not known to be poisonous but are related to species that are according to the Poisonous Plants of North Carolina database.   The Tortoise Table says that the sap of Mandevilla causes skin irritation in some people and, thus, should be avoided.   This website also suggests that since another member of the family, Oleander (Nerium oleander), is extremely toxic, it would be better to err on the side of caution and not feed the plant to your tortoise (if you have one) or eat it yourself!

 

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