I am located in Michigan. Where can I send poinsettia tissue for analysis of nutrient disorders?

Hi Geoffrey - You can check with Michigan State University. More than likely they have a testing lab. You can also check with your local extension agent for other local labs. We also like JR Peters Laboratories. Here's a link to their website: J.R. Peters.

Can u please indicate the acceptable results for leaf tissue and soil analysis??

Hi Jana -

Acceptable ranges for media analysis…..

pH 5.8-6.3
Electrical Conductivity
• SME test 1.5-2.5
• 1:2 test 0.7-1.3
• Pour-through test 2.25-3.8
- Poinsettias with dark leaves will perform better at the low end of the EC range while those with light leaves prefer an EC at the higher end of the range
Nitrate N (ppm) 100-200
Ammonium N (ppm) 0-20
Phosphorus (ppm) 5-40
Potassium (ppm) 80-180
Calcium (ppm) 100-200
Magnesium (ppm) 50-100
Sodium (ppm) 0-50


Acceptable ranges for tissue analysis…….


Nitrogen (%) 4.0-6.0
Phosphorus (%) 0.3-0.6
Potassium (%) 1.5-3.5
Calcium (%) 0.7-1.8
Magnesium (%) 0.3-1.0
Sulfur (%) 0.1-0.3
Iron (ppm) 100-300
Manganese (ppm) 60-300
Zinc (ppm) 25-60
Boron (ppm) 25-75
Copper (ppm) 2-0
Molybdenum (ppm) 1-5

Hi Geoffrey,

If you have any issues with tissue result interpretation please feel free to contact me when your tissue analysis is completed.

Best Regards,
Cari Peters
J.R. Peters Lab
866-522-5752 ext 14