En EspaŅol

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?

Share

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
Can't find the answer in our existing FAQs, submit a question to Mr. Smarty Plants.
Need help with plant identification, visit the plant identification page.
 
rate this answer
Not Yet Rated

Thursday - May 26, 2011

From: Point Pleasant, NJ
Region: Northeast
Topic: Non-Natives
Title: Promoting growth on non-native dipladinias (mandevillia) from Point Pleasant NJ
Answered by: Barbara Medford

QUESTION:

My Dipladinias were almost dead when I bought them last year, but after a little TLC, they blossomed like CRAZY in pots outside. They stopped blooming in November (I brought them into the house in September) and did well throughout the winter, with very little leaf droppage. Now they're outside again..but I bring them in when it's cold at night . I have 3 buds on a single stem for new flowers, but that's all..What should I do to promote new growth? I haven't fertilized (don't know what to use) and I haven't cut back anything (There are a million new shoots). I mist them regularly which they seem to like and don't let the soil get too wet or too dry. Also should I repot them? Thank you for your help!

ANSWER:

Mandevilla sanderi, formerly known as Dipladenia splendens, is native to the hills above Rio de Janeiro, Brazil but no longer found in its native habitat. The Lady Bird Johnson Wildflower Center is dedicated to the growth, propagation and protection of plants native not only to North America but to the areas in which those plants grow natively, so Mandevilla is out of our realm of expertise. This plant can be grown outdoors in USDA Hardiness Zones 10 and 11. In colder climates, it should be grown under glass or indoors.

Point Pleasant, in Ocean County, NJ appears to be in USDA Hardiness Zone 6a, which means your plant should definitely be considered a house plant. Whether it is hurting the plants to be taken abruptly in and out of your garden and returned to the indoors we can't say, but that may be part of the problem. Accordidng to the information we found, the misting is definitely a good idea. Your other questions are totally out of our field of experience, so we will try to find somewhere that you can get some answers.

From the Royal Horticultural Society (yes, England, they aren't native there, either) here is cultural information on Mandevilla. From Guide to Houseplants House Plant Care Tips has answers to some of your questions.

 

More Non-Natives Questions

Pruning drought-stressed butterfly plants from Kerrville TX
August 22, 2011 - Due to the drought, our butterfly bushes have dead branches. Ordinarily we prune the dormant plants in winter, but can we cut back dead branches now?
view the full question and answer

Problems with non-native yellow lantana from Elgin TX
June 17, 2012 - Why do my yellow lantana buds turn brown and do not open fully? The sprinkler system does not spray onto the lantana.
view the full question and answer

Problems with non-native privet in Austin
November 15, 2010 - My 2 privet shrubs/bushes facing the east in a shady area seem to be have less leaves and dead flowers, while across a walk way that 1 privet shrub/bush has lots of green leaves with lots of dying flo...
view the full question and answer

Red poppies to bloom in November from Round Rock TX
June 08, 2014 - Hi, I want to plant poppy seed so that they bloom in November for Veterans and Remembrance Day. Can you offer any guidance? Thanks!
view the full question and answer

Replanting of non-native Christmas Palm from Sarasota FL
November 28, 2012 - Do you know of a proven technique to plant a Christmas Palm in a built-in concrete pool deck planter box - using gravel around the soil root ball to delay the root bound condition we just ripped out?
view the full question and answer

Smarty Plants's Facebook profile Support the Wildflower Center by Donating Online or Becoming a Member today.

Mr. Smarty Plants wants you to be his Facebook friend. Click the Facebook icon to add yourself to Mr. Smarty Plants list of friends.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP
© 2014 Lady Bird Johnson Wildflower Center