Sorghum Sudan
Information on the benefits and growth habits of sorghum sudan planted as a cover crop.
Description
Family
- Grass – summer annual
- Refers to a wide range of grasses related to sorghum and sudangrass
- Usually a cross between a forage or grain sorghum and sudangrass
Cover Crop Use
- after early harvested crops
- as an emergency forage
- to add biomass to soil
- suppress nematodes (variety specific)
Growth Habits
Germination
- Requires warm soil for germination – above 12°C.
Top Growth
- Rapidly growing summer annual grass
- Wide cultivar variation – height ranges between 45 cm to over 5 m.
- Has lower leaf area than corn
Root System
- Has more secondary roots than corn
- Roots can reach depth of greater than 124 cm
Overwintering
- Easily killed by frost
Site suitability
- Extreme drought tolerance
- Prefers neutral pH but can tolerate 5.0 to 9.0
- Tolerant of salinity
Sensitivity to Herbicides: Weed Control
- There are no herbicides registered for weed control in sorghum sudan grasses. Use narrow rows and appropriate agronomic practices to establish a vigorous crop canopy as soon as possible.
Benefits and Concerns
Nutrient Management
- heavy feeder due to crop biomass
- may need additional nitrogen to aid in decomposition
Pest Management
- nematode suppression – selected varieties only
- weed suppression from competition for light, water and nutrients
Organic Matter
- can produce massive amounts of dry matter (4,000 to 5,000 lbs./acre)
- chop plant down when it reaches 1-1.2 m. to encourage tillering and deeper root growth
- manage the crop with chopping to avoid maturity as stalks gets fibrous and woody with age and slow to break down
Erosion Control
- reasonable, soil conservation alternative to summer fallowing
As Feed
- can be used as forage
- wait until mature to avoid problems with prussic acid
- do not feed if plants have been stressed or frozen
Getting Started
Establishment
- Plant in warm soils – no sooner than 2 weeks following corn
Cost & Availability
- There is a wide variation in cultivars available and some confusion with sorghum
- Cost is moderate depending on the variety
- Some varieties have nematode suppressing properties;
- Buyer Beware: Make you sure know what you're buying when getting seed
Managing the Cover Crops
- chop of mow plant when it reaches 1-1.2 m to encourage tillering and deeper root growth
- manage the crop with chopping to avoid maturity as stalks get fibrous and woody with age and slow to break down
- will set seed if not mowed
Updated: March 21, 2024
Published: August 24, 2022