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

Tuesday - August 04, 2009

From: Sonora, CA
Region: California
Topic: Compost and Mulch, Diseases and Disorders, Transplants, Herbs/Forbs
Title: Coreopsis failing to bloom in Sonora CA
Answered by: Barbara Medford

QUESTION:

My Coreopsis buds form and then die. Very few open. The plants are two and three years old, in a clay type soil. Is it possible they're getting too much water, and that is whats making the buds die and not open properly? I don't water them a whole lot, but being a xeric plant, I just wonder? Thanks!!

ANSWER:

There are 26 species of the genus Coreopsis native to North America, 9 native to California and none native to Tuolumne County. Coreopsis lanceolata (lanceleaf tickseed) is native to 2 counties north of Sonora, but that's as close as any of them come. We realize that you are probably not growing something that naturally sprouted up in your garden, but that you purchased, either in bedding pots or seeds. It just helps to give us a clue when something is not flourishing, without knowing what your soil or climate is, precisely. Since Coreopsis lanceolata is one of the more popular in the nursery trade, we will look at the growing conditions for it and see what we can find out. 

Coreopsis lanceolata (lanceleaf tickseed) is evergreen, blooms yellow April to June and is 2 to 3 ft. tall. From our webpage on this plant:

Growing Conditions

"Water Use: Medium
Light Requirement: Sun , Part Shade , Shade
Soil Moisture: Dry
CaCO3 Tolerance: None
Soil Description: Sandy, gravelly soils. Sandy, Sandy Loam, Medium Loam, Clay Loam, Clay, Acid-based, Calcareous
Conditions Comments: Lance-leaved coreopsis is the most common coreopsis and is easy to grow. It is drought tolerant but is not reliably perennial. However it self-sows readily and can become weedy. The showy golden flowers are nice in a vase and are a popular plant for visiting pollinators. It should have frequent deadheading to keep it in bloom well into the summer."

It looks like it will grow in clay and can even become pretty aggressive. So, we have some questions for you to ask yourself in trying to figure out what is going on? Have the coreopsis ever bloomed in what you consider a normal way in the two to three years you have been growing them? If not, you got off on the wrong foot, or stem, as it were, from the start. It is a xeric plant, but most of the West has been having a record-breaking heat and drought cycle and this may be inhibiting the blooms. With clay soil and xeric plants, you need to be sure they have the water to survive, but that their roots are not standing in water. Addition of some organic material (compost, for instance) to clay soil before planting can make a big difference, not just in drainage, but in permitting the roots to access necessary trace elements in the soil. If you suspect drainage is the problem, try working some compost in the soil around the plants now, covering the area with shredded bark mulch, and see if you can cut down on the water. 

Another thought is fertilization. Everyone is tempted to try to cure any plant problem with a quick dose of fertilizer. In the first place, a native plant in its correct habitat should not need fertilizer, it is already adapted to the dirt in which it is growing. You should never fertilize a plant that is stressed, which it sounds like yours is, and NEVER use a high nitrogen fertilizer. That is meant to encourage lots of green leaves, as in grass, and not blooms. 

Beyond those comments, about all we can offer is to point out that the plant's normal blooming cycle is from April to June, but, as you saw in the Conditions Comments above, frequent deadheading will encourage blooming into summer.  Deadheading encourages further blooming because a plant's prime object is to survive, which means reproducing, which means seeds, which means blooms. If the blooms are removed, the plant will try to bloom again until it runs out of energy. It takes an enormous amount of energy for a plant to bloom and set seed, and there are limits to how long it can continue. 

If you have seen no insects that appear to be damaging the buds, about all we can suggest is to experiment and see if cooling the roots with mulch, and trimming off any undeveloped buds will help. Although this plant is not considered reliably perennial, you might take the opportunity this winter of digging up the clumps of plants, dividing them and, while they are out of the ground, amending the soil as suggested above. 

From our Native Plant Database Image Gallery:


Coreopsis lanceolata

Coreopsis lanceolata

Coreopsis lanceolata

Coreopsis lanceolata

 

 

 

More Compost and Mulch Questions

Transplanting redbud from field in Edmond, OK
March 30, 2009 - I want to transplant a small redbud from a field to my yard. The trunk diam is about 1.5" and the tree is about 4' tall. What is the best way to do this? Should I plant it in a pot first?
view the full question and answer

Browning leaves on non-native Burford holly
August 22, 2008 - I have several dwarf Burford hollies whose leaves are browning. The individual leaves have colors of green, dark brown to light brown extending from the stem. Any ideas?
view the full question and answer

Poor drainage in clay soils in Langhorne PA
September 15, 2009 - Our backyard has very poor drainage, to the point of up to 3 inches of rain can sit until it is evaporated. Talking to neighbors, they informed us that there use to be a terrain that ran through our ...
view the full question and answer

Stumps of fallen oaks in Hurricane Irene from Newton PA
September 03, 2011 - Two large red oaks fell in the woods in our yard in Newtown PA due to Hurricane Irene. The trees have been removed, but the stumps remain. Please can you recommend some fast-growing, attractive, nativ...
view the full question and answer

Black-eyed Susans in potting soil on ground
November 12, 2010 - I would like to know if black eyed susans can be planted in just potting soil instead of mixing it in with dirt from the ground? I don't want to leave it in the pots. I want to plant it, but the grou...
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