Kentucky bluegrass is a cool-season turfgrass in the Poaceae family. It has a fine texture, attractive color, strong regeneration ability, and forms a compact and elastic lawn green space after maturing. In addition, it is cold-resistant, shade-tolerant, pruning-resistant, and has a long green period. It has become one of the important turfgrass species in temperate regions and is widely used in gardening and ecological greening and beautification.
Application of plant growth regulators on Kentucky bluegrass:
- Promote seed germination
Soaking seeds with 150~300mg/L Ethephon solution for 24 hours can improve the germination potential of Kentucky bluegrass seeds and promote the growth of the embryo and radicle of both. Soaking Kentucky bluegrass seeds with 100~200mg/L gibberellic acid solution for 24 hours can promote seed germination and seedling growth.
- Promote growth and early greening
At the early stage of Kentucky bluegrass greening, spraying the lawn with 42.5mg/L gibberellic acid solution on the leaves can accelerate its growth and early greening, and the efficacy can last for about 1 month. In addition, spraying Kentucky bluegrass with 30~50mg/L gibberellic acid solution on the leaves, combined with water and fertilizer management, can accelerate lawn growth and complete the greening process early
- Regulate growth and reduce manual pruning
About 20 days after the Kentucky bluegrass seedlings emerge from the soil, first spray the leaves with 150mg/L Paclobutrazol solution once, and then spray 200mg/L Paclobutrazol solution 3 times every 5 days or so, which can achieve the effect of controlling growth and dwarfing. In addition, after spraying Kentucky bluegrass wall carpet with 0.9% Daminozide (B9) solution once every two months, the number of leaves per plant decreased significantly, and the number of roots increased accordingly, which can achieve the ideal effect of inhibiting leaf growth and enhancing root growth.
The lawn grows fast in summer, and the mowing frequency is high, which is labor-intensive and time-consuming. Using growth retardants within 1 to 2 days after mowing, such as spraying 200~250mg/L Uniconazole solution on the leaves, can effectively slow down the growth rate and reduce the mowing frequency.
- Improve stress resistance
40 days after Kentucky bluegrass is sown in autumn (three-leaf stage), prune with 6cm stubble, and spray Paclobutrazol (25~50mg/mm²) or Uniconazole (20~40mg/m²) solution 2 days after the first pruning, which helps to improve the cold resistance of Kentucky bluegrass lawns. The effect is long-lasting, nearly two months, and can be used for young lawns to resist frost damage and extend the growth period (green period) of winter lawns. In addition, spraying Paclobutrazol (25~50mg/m²) or Uniconazole (20~40mg/m²) solution on Kentucky bluegrass before the high temperature in summer can help them survive the summer smoothly.
In arid areas, spraying 0.3% Daminozide (B9) or 0.2% Paclobutrazol solution on the leaves of Kentucky bluegrass lawns can keep the lawn green even in very dry conditions (the absolute soil moisture content drops to 14%).
Furthermore, for Kentucky bluegrass in shaded conditions, spraying 100~200mg/L Uniconazole solution on the lawn can effectively improve the shade tolerance of the lawn, the lawn color becomes greener, the leaf thickness and width increase, the stem nodes become shorter, and the plant resistance is also improved.