Ways of Seed Coating & Seed Pelleting  -  A Comparison



The Art of Seed Pelleting   -  Coated Seed     Lawn Seed Pelleting

Efficient use of the resource seed as far as the sensitive and sparing refinement of seed are still actual issues in the seed refining processes. Several solutions have been found over the years and have been made available for industrial processing  -   with very different features after having passed these processes. Finally the target was and is to create new helpfull properties, don‘t waste seed and make the seed surviving all processses on the way from harvest to sowing.

Seed coating  means that each single ‚naked‘ seed corn is coated in a way that different layers of coating material are brought onto the seed corn.  Some layers may have the same material and simply need more than one run, different layers with different functions are possible too. Finally germination capability, protection against drying out or against becoming birdfeed are targets  -  next to the specific weight increase needed to improve the resistance against displacement by wind or rain.

Another way of seed pelleting is making use of extruders  where the pasty seed  - matrix - mass  is pressed through an opening hole to produce the  pellets. This is an easy way to produce cost effective higher weight pellets with protective properties against wind and rain displacement and with the capability to germinate ‚on soil‘  -  i. e. ideal for lawn repair. But extruder made pellets could not gain acceptance because the share of pre-damaged seed corns is significant. Pressure, temperature increase and shearforces during the process are the reason for this negative impact on the seed corns.

The instant seed process  of seed pelleting  - especially of lawn seed pelleting -  was developed starting in 2011 and meanwhile is industrially scalable.  Target was to combine advantages  -   the cost effectiveness of extruder pelleting and the seed protective features of the (layer) coating process.  The specific weight of the produced seed pellets is slightly higher than water and guarantees good soil contact as far as resistance against wind and rain displacement  -  and so ideally fits to the needs of  i.e. lawn repair where the seed is not brought under the soil. Specific seed weight simply can be increased for special reasons  i.e. bringing out the seed by a plane or for sowing on slopes and in rainy regions.  No temperature increase, pressure or shearing forces are damaging the seed corns and so the germination features of the used seed corns are completely kept alive  -  no ‘stress‘ for the seed.

All processes described above are followed by a drying process in order to extract the water out of the pasty mass and to prepare the seed for being packed and stored. Temperature is  kept below 35o Celsius (95 degrees Fahrenheit) to save germination capabilities.