Tech Notes Issue 8
Late Season Fertilization
Fall is a time for summer stress recovery and in the case of athletic fields a time to recover from wear injury. Late fall fertilisation is critical in promoting recovery and preparing the turf for the coming spring season. It is difficult to be specific on the fertiliser, rate, and timing because climatic and local conditions.
On both cool and warm season turfgrasses fertilisation should be continued until shoot growth has ceased. Granular slow release fertilisers (30 to 50% slow release) are popular for fall applications. On warm season turfgrasses, if winter injury is a potential problem, nitrogen should be in a form not to stimulate growth beyond normal shoot growth periods. In this case, a more quick release nitrogen fertiliser might be used. On soils high in sand, a slow release nitrogen fertiliser would be recommended to minimise any potential to leaching.
In regard to phosphorus and potassium, a balanced fertiliser (N:P:K) would be suggested for cool season turfgrasses. For warm season turfgrasses, a similar recommendation would be suggested. On couchgrass, a 4:1:6 (N:P:K) fertiliser has been found to improve winter hardiness.
|
Parameter
|
Cool Season Turfgrasses |
Warm Season Turfgrasses |
| More Efficient Photosynthate (more carbohydrates to roots, shoots and stems) |
Yes |
Potentially |
| Reduced mowing (during spring, less flush of growth) |
Yes |
Yes |
| Stimulate Root Growth |
Yes |
Yes |
| Improves shoot density |
Yes |
Yes |
| Longer fall color retention |
Yes |
Yes |
| Early spring green-up |
Yes |
Yes |
| Fewer weed problems |
Yes |
Undocumented |
| Fewer summer disease problems |
Yes |
Undocumented |
| Improved summer performance |
Yes |
Yes |
| Increased Poa annua invasion |
Undocumented |
Undocumented |
| Decreased cold tolerance |
No |
No, unless nitrogen applied at a time that promotes growth over hardening |