Home  |  Contact Us  |  Join our Mailing List
Viaspace Home Page OTCQB Stock Symbol: VSPC
Current Price: $
Full Stock Quote

Giant King Grass: Grow and Harvest


Giant King Grass is a fast growing, high yield, perennial grass with many applications including bioenergy and animal feed. Giant King Grass is not genetically modified and is not invasive. It grows in a variety of soil conditions and does not compete with food crops. Another significant advantage of Giant King Grass is that it can be harvested in the first year, where other crops may take one or two years before the first harvest.

Giant King Grass is best grown in tropical and subtropical regions with plenty of sunshine and rain per year (or irrigation). Giant King Grass is perennial and will survive a frost, but not a prolonged freeze. Fertilizer requirements are modest and no pesticide is required in the current cultivation. The total water requirements are approximately 100 mm (4 inches) per month rainfall equivalent. Flood irrigation, sprinklers, water cannons or drip tapes and tubes are irrigation options.

Each different application of Giant King Grass requires slightly different agriculture and different harvesting times. For generating electricity using direct combustion and making energy pellets for cofiring with coal, the main objective is to maximize total energy content and this means maximizing biomass yield per acre. This is achieved by letting the Giant King Grass grow tall with woody stalks. Harvesting is at approximately 6 months. Testing has shown that the maximum ethanol production is achieved at six months old. In a tropical area, there can be two harvests per year.
Giant King Grass at six months is typically 14-17 feet (4.3-5.2m) tall Giant King Grass at six months is typically 14-17 feet (4.3-5.2m) tall

Giant King Grass at six months is typically 14-17 feet (4.3-5.2m) tall



Giant King Grass is an excellent feedstock for anaerobic digestion that produces biogas that can fuel an engine generator to produce electricity, or can be upgraded and injected into the natural gas pipeline. The lignin in tall Giant King Grass, that gives us the strength to stand up, inhibits anaerobic digestion. Therefore the grass should be harvested earlier when the stalks are still green and not woody. Any Giant King Grass younger than three months old is suitable for anaerobic digestion, but the maximum biogas yield per acre of land is at 90 days old. In a tropical area with sufficient rainfall or irrigation there can be four harvests per year.
Giant King Grass at 70-90 days Giant King Grass at 70-90 days

Giant King Grass at 70 and 90 days old. Both are suitable for anaerobic digestion.


For animal feed, the primary considerations are high nutritional value including protein and palatability for the animals. In general, animal feed harvests are at 40 to 60 days old at heights from 5 feet to 7 feet tall (1.5-2.1m). There are several approaches to animal feed. The grass can be cut and fed immediately to animals without chopping. It can be chopped and fed as fresh chop or made into silage. It can be dried and baled into hay or made into animal feed pellets. Giant King Grass is best used as a “cut and carry” animal feed. Grazing is possible, but it must be managed in fenced areas to make sure that all of the grass is uniformly eaten, because any uneaten grass will soon grow very tall and not be suitable for animal feed.

Giant King Grass at 40-60 days Giant King Grass at 40-60 days

Giant King Grass at 70 and 90 days old. Both are suitable for anaerobic digestion.


Because the animal feed grass will never be allowed to grow tall, it can be planted more densely to increase yield per acre. Protein content can be increased with increased nitrogen fertilizer. Giant King Grass provides many of the nutrition requirements for cattle and dairy cows. It has fiber, protein and good energy content and is willingly eaten by the animals. In the US, dairy cows and cattle are fed a mixed daily ration of different feeds to give the proper nutrition. Giant King Grass can replace expensive feeds in the ration and therefore reduce feeding costs while maintaining good nutrition.

Giant King Grass is grown from stalk cuttings like sugarcane. It is not grown from seed. VIASPACE maintains nurseries in California and in Hawaii to provide cuttings for customers. Typically a customer receives Giant King Grass cuttings from VIASPACE sufficient for 5 acres (2 ha) initial plot that serves as a proof of concept demonstration, training ground for employees and a local nursery for propagation of the production fields. 1 acre of Giant King Grass nursery can propagate into 50 or more acres of production fields every six months. A large plantation can be fully established in 12 to 24 months which is less time than it takes to build a power plant. VIASPACE will train the customer in all aspects of Giant King Grass agriculture. The yield of Giant King Grass depends on the time between harvests. For example, a six-month harvest of tall Giant King Grass, one can expect to obtain 80 or more US tons per acre (180 metric tons per hectare) of fresh grass at approximately 70-75% moisture. For two harvests per year, double these figures. Giant King Grass regrows after cutting for seven years or more.

Giant King Grass has been approved for use throughout the United States including Hawaii. The US Department of Agriculture inspects all shipments to foreign countries and issues a phytosanitary certificate stating that the Giant King Grass is free of pests and disease.
phytosanitary certificate

Giant King Grass has been shipped to and is growing in several countries around the world.