Special Rose Care Posts

Post from: Ralph Stream, District Director

TIP: Soil Testing Your Roses

Soil Testing Your Roses

Soil Test FORM- Waters Lab – 5-17


Post from: Phil Paul, MR

Rose Cane Canker and Dieback in Roses

A look into a complex and confusing fungus. A help to Consulting Rosarians.

 


What’s Wrong With My Rose??
By: Gaye Hammond Master Rosarian – Houston Rose Society

Not too long ago I had the great good fortune to attend a lecture presented by Dr. Ed Bush, Associate Professor of Ornamental Horticulture at Louisiana State University titled “What’s Wrong with My Rose?”   According to Dr. Bush, most of the time a rose will send visible signals that something is wrong.  Rose gardeners know to look for disease symptoms like blackspot and powdery mildew and damage caused by insects, but plant changes caused by nutrient deficiencies can be subtle and may go unnoticed in the early stages.  The chart below provides a quick reference to helping diagnose nutrient imbalances in roses.

 

If your roses display symptoms from this chart, I would encourage you to send a soil sample to Texas A&M’s Soil, Water and Forage Laboratory for confirmation before taking remedial action to rectify any nutrient imbalance.  A soil test will not only identify nutrient deficiencies – it will also identify any nutrient levels that are too high as well as make recommendations for bringing the soil nutrient profile back into balance. Soil tests are inexpensive and the results are usually received within a week.  Forms and instructions for submitting a soil sample are available online at http://soiltesting.tamu.edu.

For those residing outside of Texas, contact your local Extension Service or Master Gardener Association for forms/instructions on submitting soil samples.

Figure 1 Yellowing between leaf veins can be caused by magnesium and manganese deficiencies.  Photo courtesy of Dr. Ed Bush, Louisiana State University

WHAT’S WRONG WITH MY ROSE?

The highlighted cells in this chart represent the suspected deficient element (nutrient).  Abbreviations for the elements (nutrients) included in the chart are:

“N”                  Nitrogen                                               “Cu”                Copper

“P”                   Phosphorous                                        “Zn”                Zinc

“K”                  Potassium                                            “B”                  Boron

“Mg”                Magnesium                                          “Mo”               Molybdenum

“Fe”                 Iron                                                      “Mn”               Manganese

 

Symptom Suspected Deficient Element (Nutrient) Over Fertilization

 

N P K Mg Fe Cu Zn B Mo Mn  Over Fertilization
Yellowing of younger leaves          XX XX
Yellowing of middle leaves                  XX  
Yellowing of older leaves  XX    XX  XX      XX      
Yellowing between veins        XX            XX
Old leaves drop  XX                  
Leaf curls over        XX            
Leaf curls under      XX      XX          XXXXX
Leaf tips burn (younger leaves)                XX    
Leaf tips burn (older leaves)                    
Young leaves wrinkle and curl      XX        XX  XX  XX  
Dead areas in the leaves      XX  XX  XX    XX      XX
Leaf growth stunted  XX XX                 
Dark green / purplish leaves and stems    XX                
Pale green leaf color  XX                XX  
Leaf spotting              XX      
Spindly plant  XX                  
Soft stems  XX    XX              
Hard / brittle stems    XX XX               
Growing tips die      XX          XX    
Stunted root growth    XX                
Wilting            XX        

 

Chart courtesy of Dr. Ed Bush, Louisiana State University