2. Polyon test results, France
Method
Factors studied:
| Company | Fertiliser |
Formula
|
Longevity
|
Usage rate
|
| Scotts | Osmocote | 17-10-10 | 12/14 months | 5kg/m3 |
| Pursell | Polyon | 17-5-11 | 12/14 months | 5kg/m3 |
| Pursell | Polyon+ Coated Ammonium Phosphate |
17-5-11 + 12-42-0 |
12/14 months 3/4 months |
5kg/m3 +1kg/m3 |
Plants used:
| Species | Nature of young plant |
Supplier
|
| Nerium oleander 'Provence' |
Alveole dia. 5cm | Plant Sud |
| X Cupressocyparis leylandii | 2 BR 15/25 | Renault |
| Pruns lauro 'Rotundifolia' |
2 BR 30/45 | Renault |
Potting:
4 litre containers, into a substrate consisting of:
• 40% White peat
• 50% Composted bark
• 10% Tile waste
Setting up of experiment:
In four complete blocks;
3 species,
3 modalities,
24 plants per cell,
+ borders,
this being a total of 936 containers.
Discussion
The results presented show that:
• The release of the nutrients from Polyon is slower than from Osmocote over the first three months of its being incorporated in the pot.
• Over 5 months the two products are more comparable, the granules containing at this time approximately 40-50% of their original content, thus showing that Polyon’s release rate increases during the second half of the growing season.
• This difference in performance can be seen as an advantage for the species, such as Nerium oleander and Prunus laurocerasus, that benefit from this delayed release and continued to grow until the end of the test period.
• For the two aforementioned species fertilising using 5kg/m3 of Polyon gives better results than fertilising with Osmocote, although this cannot be shown statistically.
• This difference in growth is made greater for these species by the addition of 1kg/m3 of Ammonium Phosphate to the Polyon-fed pots especially in the case of Nerium oleander.
• The three modes of fertilising, however, give identical results for X Cupressocyparis leylandii.
Conclusions
It appears from the entirety of these results that the speed of nutrients release from Polyon is slower than Osmocote over a three month period but then accelerates which particularly benefits growth at the end of the season for Nerium oleander and Prunus laurocerasus.
This difference is made greater by adding 1kg/m3 coated Ammonium Phosphate, which provides nutrients at the beginning of the growing period.
For X Cupressocyparis leylandii on the other hand the three modes of fertilising give identical results.
POLYON TEST RESULTS, NORTH OF FRANCE
Conclusion
Comparison of Osmocote Plus 16-8-12 and Polyon 18-6-12 has not shown significant differences for the growth of the plants.
Differences become more apparent when the substrates are analysed: Osmocote Plus produced very high peaks of conductivity (above 1.50 mS) while Polyon remained at a low level. The pH of the substrates remained at an acceptable level for the assimilation of nutrients (between 5 and 7).
Chemical analysis of the elements remaining in the Polyon granules gave the remaining contents of the granule to be 50% of the initial nutrient content.
The 8-9 month longevity is perhaps too great for the central region of France since at the end of September 50% of the NPK content remained in the granule, this at a period when the temperature is unfavourable for release.
These tests were undertaken for the 1999 season for which climate records are available.
TECHNICAL CHARACTERISTICS OF POLYON PRODUCTS
Four trials in official research centres:
• Two in ornamental nurseries
• One on perennial plants
• One on Hydrangea
Forty commercial trials:
• One in propagator nursery,
• Fifteen in ornamental nurseries,
• Two in fruit nurseries,
• Two in perennial nurseries;
• One on Cyclamen,
• Five on bedding plants,
• Five on Chrysanthemum,
• Two on Hibiscus,
• Five on Geranium,
• Three on aromatic plants.
Subjects of study:
• Longevity,
• Conductivity of leachate,
• Nutrients remaining in granule,
• Growth.
RESULTS
POLYON > OSMOCOTE
Polyon<Osmocote Plus Polyon=Osmocote Plus Polyon>Osmocote Plus
In 10% of cases In 60% of cases In 30% of cases
These results are based on:
- trials in official research centres
- comments from commercial growers
CONCLUSIONS
In comparison to Osmocote
- Conductivity much lower (1.5 to 4 times lower than Osmocote) showing a more controlled release,
- Greater homogeneity of release (from statistics based on 1000 granules),
- Greater resistance to extremes of temperature,
- Loss negligeable (less than with Osmocote),
- Longevity more accurate.
POLYON’S CHARACTERISTICS
1. Very reliable,
2. Lower conductivity – less over-release,
3. Good resistance to heat and mechanical abuse,
4. Good quality for growth,
5. Homogeneous plants,
6. Good plant growth,
7. Good root development,
Long period of flowering.
