Accelerating Grass Seed Germination for Rolled Turf Production
Rolled turf manufacturing is challenging. Fast germination, dense grass, and short cultivation cycles are essential for an efficient turnover and profitability. Sonication is a highly effective technique to boost turf grass cultivation. Controlled exposure to high-intensity, low-frequency ultrasound facilitates nutrient uptake, germination, sprouting and growth of grass lawns and rolled turfs.
Ultrasonically-Promoted Seed Germination
Controlled sonication creates minute cracks and holes in the seed’s coat (the so-called testa), which leads to an accelerated water absorption. The increased water absorption improves seed viability by activating metabolic enzymes. When enriched with fertilizer, the sonicated seeds not only are soaked but also nourished with essential nutrients for a quick and robust growth of grass and crops.
Hielscher sonicators allow the precisely controlled exposure of seed to the optimal intensity of ultrasound. Flow-through treatment enables for an efficacious and reproducible sonication ensuring reproducible effects for consistent quality.

Industrial sonicator UIP2000hdT for the inline priming of seeds to improve germination rates.

Schematic summary of the ultrasound effects on seeds and the mechanisms of action.
Study and scheme: ©Nogueira et al., 2023
Sonication and its Effects on Grass Seed Germination
Research and scale-up studies have demonstrated the efficacy of ultrasonication in promoting seed germination across various species, including grass types of the Poaceae family such as Lolium perenne (perennial ryegrass) and Festuca arundinacea (tall fescue), pulses, and other crops.
Key mechanisms of Ultrasonically-Promoted Germination:
- Seed coat modification: Short-duration sonication increases permeability of the seed coat (testa), allowing for more efficient water and oxygen uptake. Both are essential for initiating metabolic activity and sprouting.
- Stimulation of enzymatic activity: Sonication has been shown to up-regulate enzymes such as α-amylase, accelerating the mobilization of starch reserves within the endosperm.
- Disruption of dormancy: Especially relevant for hard or semi-dormant seed varieties, controlled sonication helps to overcome physical dormancy by micro-fracturing the outer layers, thus removing mechanical barriers to radicle protrusion.
Low-intensity sonication at an ultrasound frequency of 20 kHz significantly enhances germination rate and early root development in cereal and forage grasses. These results can be transposed at the seedling stage under hydroponic and soil conditions.

Ultrasonic flow cell with cooling jacket at the industrial 6000 watts sonicator UIP6000hdT for large scale processing under precisely controlled conditions.
High Performance Ultrasonicators
Hielscher Ultrasonics develops and manufactures probe-type sonicators renowned for their ultrasound performance, precision, robustness, and scalability. Hielscher sonicators operate at precisely tunable ultrasonic intensities, generating vibrations and cavitation that facilitate mass transfer and cell permeability. In the context of seed germination, Hielscher sonicators are used to prime seeds by disrupting the seed coat or stimulating enzymatic activity, thereby breaking dormancy, accelerating water uptake and promoting uniform sprouting. Real-time process control, programmable sonication settings, and temperature control are essential features for reproducibility in biological applications. With these advantages, Hielscher ultrasonicators provide competitive advances in agriculture and seed science.
- high efficiency
- state-of-the-art technology
- reliability & robustness
- adjustable, precise process control
- batch & inline
- for any volume
- intelligent software
- smart features (e.g., programmable, data protocoling, remote control)
- easy and safe to operate
- low maintenance
- CIP (clean-in-place)
Design, Manufacturing and Consulting – Quality Made in Germany
Hielscher ultrasonicators are well-known for their highest quality and design standards. Robustness and easy operation allow the smooth integration of our ultrasonicators into industrial facilities. Rough conditions and demanding environments are easily handled by Hielscher ultrasonicators.
Hielscher Ultrasonics is an ISO certified company and put special emphasis on high-performance ultrasonicators featuring state-of-the-art technology and user-friendliness. Of course, Hielscher ultrasonicators are CE compliant and meet the requirements of UL, CSA and RoHs.
The table below gives you an indication of the approximate processing capacity of our ultrasonicators:
Batch Volume | Flow Rate | Recommended Devices |
---|---|---|
1 to 500mL | 10 to 200mL/min | UP100H |
10 to 2000mL | 20 to 400mL/min | UP200Ht, UP400St |
0.1 to 20L | 0.2 to 4L/min | UIP2000hdT |
10 to 100L | 2 to 10L/min | UIP4000hdT |
15 to 150L | 3 to 15L/min | UIP6000hdT |
n.a. | 10 to 100L/min | UIP16000hdT |
n.a. | larger | cluster of UIP16000hdT |
Literature / References
- Yaldagard, Maryam; Mortazavi, Seyed; Tabatabaie, Farideh (2008): Influence of ultrasonic stimulation on the germination of barley seed and its alpha-amylase activity. African Journal of Biotechnology 7(14), 2008. 2465-2471.
- Yaldagard, M., Mortazavi, S.A. and Tabatabaie, F. (2008): Application of Ultrasonic Waves as a Priming Technique for Accelerating and Enhancing the Germination of Barley Seed: Optimization of Method by the Taguchi Approach. Journal of the Institute of Brewing, 114: 14-21.
- Godlewska, K.; Biesiada, A.; Michalak, I.; Pacyga, P. (2020): The Effect of Botanical Extracts Obtained through Ultrasound-Assisted Extraction on White Head Cabbage (Brassica Oleracea L. Var. Capitata L.) Seedlings Grown under Controlled Conditions. Sustainability 2020, 12, 1871.
- Ranjbari, A. & Kashaninejad, Mahdi; Aalami, Mehran; Khomeiri, Morteza; Gharekhani, Mehdi (2013): Effect of ultrasonic pre-treatment on water absorption characteristics of chickpeas (Cicer arietinum). Latin American applied research 43, 2013. 153-159.
- Nogueira, António; Puga, Hélder; Gerós, Hernâni; Teixeira, António (2023): Seed germination and seedling development assisted by ultrasound: gaps and future research directions. Journal of the Science of Food and Agriculture 104, 2023.
Frequently Asked Questions
What is Seed Priming?
Seed priming is a controlled pre-germination treatment that involves partial hydration of seeds to activate metabolic processes without initiating radicle emergence, enhancing germination speed, uniformity, and stress tolerance.
What is the Difference Between Physical/Mechanical and Chemical Seed Priming?
Physical/mechanical priming uses physical agents (e.g., temperature, magnetic fields, ultrasound) to improve seed performance. Chemical priming employs bioactive compounds (e.g., salts, hormones, or antioxidants) that modulate biochemical pathways to enhance stress resilience or germination.
What is Osmo-Priming?
Osmo-priming involves soaking seeds in osmotic solutions (e.g., polyethylene glycol or mannitol) with low water potential, allowing controlled water uptake and metabolic activation under non-germinating conditions.
What is Halo-Priming?
Halo-priming uses inorganic salt solutions (commonly NaCl, KNO₃, or CaCl₂) to treat seeds, promoting ionic and osmotic stress adaptation and improving tolerance to salinity and drought during early growth.

Hielscher Ultrasonics manufactures high-performance ultrasonic homogenizers from lab to industrial size.