How to Grow and Care for Switchgrass

Switchgrass (Panicum virgatum) is a native North American perennial warm season grass that is an excellent choice for erosion control, wildlife habitat, and biomass production. Growing switchgrass is relatively easy, as it is hardy, adaptable to various soil types and requires minimal care once established. With proper site selection, soil preparation, planting, and maintenance, you can have a thriving stand of switchgrass.

Choosing a Switchgrass Variety

When selecting a switchgrass variety, consider your climate and intended use. Lowland varieties are better suited to warmer southern climates, while upland northern varieties tolerate colder winters. Lowland types generally have higher biomass yields but are less drought tolerant. Some recommended varieties include:

Alamo – High-yielding lowland variety ideal for bioenergy production in southern regions.
Cave-in-Rock – Upland variety good for northern areas, known for drought tolerance.
Kanlow – Lowland type with excellent biomass production for southern climates.
Blackwell – Upland strain tolerant of poor soils, popular for conservation uses.
Shelter – Upland type developed for northern growing conditions and wildlife habitat.

Contact your local agricultural extension office for advice on the best switchgrass cultivars for your specific area.

Selecting a Site with Optimal Growing Conditions

Choosing an appropriate planting site is key to switchgrass success. Ideal conditions include:

Full Sun – Switchgrass thrives in full sunlight.
Well-Drained Soil – Good drainage is essential, avoid soggy sites prone to flooding.
pH 5.0-8.0 – Favors neutral to slightly acidic soils, but can tolerate pH from 5.0-8.0.
Open Areas – Plant switchgrass away from shrubs and trees to reduce competition.
Slopes/Marginal Land – Excellent for erosion control on slopes or marginal/idle cropland.

Select a site with as many optimal conditions as possible for vigorous switchgrass growth.

Preparing the Site

Proper site preparation sets the stage for a flourishing stand of switchgrass:

Eliminate Existing Vegetation – Remove competing weeds, grasses and old crops through tillage and herbicide applications. Glyphosate can provide pre-plant weed control.
Install Drainage – Improve drainage in poorly drained sites with tile drainage or ditches.
Soil Testing – Test soil and amend according to recommendations to optimize fertility. Switchgrass prefers pH around 6.0.
Prepare Seedbed – Cultivate area to create a firm, weed-free seedbed. The top 3-6 inches of soil should be loose and smooth.
Weed Control – Manage weeds prior to planting through cultivation and herbicides. Reduce competition for young grass seedlings.

Taking time to properly prepare the site leads to better stand establishment and growth.

When to Plant Switchgrass

Switchgrass should be seeded during its optimal spring or early summer planting window:

Spring Planting – Sow seeds from late April to early June. Aim for soil temperatures around 50-65°F.
Early Summer Planting – Seeding can extend into early summer when soil temperatures are 65-80°F.
Weed Control – Manage weeds prior to seeding so young grass isn’t overwhelmed.
Moisture – Ensure adequate soil moisture at planting time and irrigate if conditions are dry.

Adhere to the recommended spring/early summer planting window for your region to give switchgrass the best start possible.

How to Plant Switchgrass

Proper seeding techniques help guarantee switchgrass success:

Seeding Rate – Seed at a rate of 3-6 lbs per acre, adjusting for purity and germination rates.
Planting Depth – Sow seeds 1/4-1/2 inches deep in fine textured soils, 1/2-3/4 inch deep in sandy soils.
Broadcast Seeding – Use broadcast seeders or spread seed by hand in small areas. Ensure even distribution.
Cultipacking – Use a cultipacker after broadcast seeding to press seeds firmly into soil.
No-Till Drilling – Plant seeds directly into untilled ground using a no-till drill for good seed-to-soil contact.
Irrigate – Water thoroughly after seeding to moisten soil to a 3-4 inch depth.

Proper planting techniques help ensure good germination and establishment.

Switchgrass Seedling Care

Caring for young switchgrass seedlings encourages vigorous early growth:

Weed Control – Manage competitive weeds through mowing and herbicide applications after seedlings emerge.
Maintain Moisture – Water during dry periods to keep soil moist 1-2 inches down in seedling root zone.
Apply Fertilizer – Fertilize sparingly with nitrogen once seedlings are 3-4 inches tall if soils are infertile.
Monitor Growth – Watch for grassy weeds that may overwhelm delicate new seedlings.
Reseed Bare Areas – Reseed spots that fail to establish to thicken up stand.

Attentive care while plants are young leads to a lush, thriving switchgrass field.

Maintaining an Established Switchgrass Stand

Once established, switchgrass requires minimal maintenance:

Weed Control – Use selective herbicides or frequent mowing to control weeds in established stands.
Mow/Harvest – Mowing or harvesting once after frost kills switchgrass provides weed control and removes biomass. Leave 6-8 inch stubble height.
Prescribed Burns – Burning every 3-5 years reduces dead material, controls weeds and improves wildlife habitat. Burn in early spring before greenup.
Fertilization – Avoid excess nitrogen which can encourage grass competition. Only fertilize established stands when deficient.
Monitor for Pests – Watch for pests and diseases which are rare but can occasionally be troublesome. Scout fields and treat as needed.

Proper maintenance keeps switchgrass productive for 15 years or longer.

Troubleshooting Common Switchgrass Problems

Switchgrass is relatively trouble-free, but may experience occasional issues:

Poor Germination

Cause – Seeding too deep, allowing soil surface to crust over, inadequate moisture
Solution – Maintain shallower planting depth, cultipack after planting, irrigate to improve germination

Weak Seedling Growth

Cause – Excessive weed competition for sunlight, water and nutrients
Solution – Control weeds with mowing and herbicides until grass is established

Thin Stand Density

Cause – Low seeding rate, poor germination, winterkill of seedlings
Solution – Increase seeding rate, reseed bare areas in spring to thicken stand

Weed Encroachment

Cause – Insufficient weed control during establishment
Solution – Utilize integrated weed management with proper mowing, herbicides, and prescribed burns

Catching issues early allows for corrective action to get switchgrass growing vigorouusly again.

Harvesting Switchgrass for Bioenergy Production

Managing switchgrass as a biomass energy crop involves proper harvest and storage:

Timing – Harvest after frost once nutrient translocation to the roots occurs, typically November to March.
Mowing Height – Mow at 6-8 inch cutting height using sicklebar mower or rotary disk mower conditioner when seedheads are fully emerged.
Raking & Baling – Rake mowed material into windrows then bale using large round or rectangular balers within 24-48 hours.
Storage – Store bales under cover or wrap in UV resistant plastic to protect from precipitation and UV breakdown until use.
Transportation – Haul bales carefully to avoid dry matter losses from handling and weathering.

Proper harvest, storage and handling ensures optimum biomass quality for bioenergy applications.

Switchgrass for Forage Use

When managed for forage, follow these recommendations:

Variety Selection – Choose upland switchgrass varieties as they have finer stems and higher digestibility than lowland types.
Cutting Height – For hay/silage, mow at 8-10 inches when plants are 2-3 feet tall, typically late June. Leave stubble height of 6 inches.
Harvesting – Make 2-3 cuttings per year starting in late June, allowing 6 weeks regrowth between cuttings.
Forage Quality – Cut, condition and dry promptly. Cutting late decreases forage quality.
Grazing – Begin grazing at 18-24 inches during late spring once plants are firmly established. Do not overgraze.

Properly harvesting switchgrass for forage provides excellent fodder for livestock.

Switchgrass for Wildlife Habitat

Switchgrass provides excellent cover and food resources for wildlife:

Stand Density – Maintain lightly grazed stands at 60% canopy cover to provide protective cover adjacent to open areas.
Field Size – Large fields over 30 acres provide habitat for grassland birds. Smaller fields benefit other wildlife.
Burning – Conduct burns in spring every 3-5 years to improve structure for nesting and brood rearing.
Mowing – If not burning, mow once annually after frost to maintain stand. Leave 6-8 inch stubble.
Woody Growth – Control invading shrubs and trees to maintain open grassland habitat preferred by wildlife.
Reduced Pesticide Use – Minimize pesticide use which can reduce insect populations relied on by wildlife for food.

Properly managed switchgrass provides essential habitat for grassland birds, mammals and other wildlife species.

Frequently Asked Questions About Growing Switchgrass

Growing switchgrass for the first time? Here are answers to some common questions:

How long does it take for switchgrass to establish?

It typically takes switchgrass 1-2 growing seasons to become fully established. Emergence is fairly rapid, but plants remain small in their seedling year. Robust tillering and growth develops during the second year.

Does switchgrass need a lot of water?

Once established, switchgrass is relatively drought tolerant and doesn’t require much water. However, consistent moisture during establishment improves success, particularly on marginal sites. Irrigation is recommended if seeding during hot, dry conditions.

How often should switchgrass be fertilized?

Switchgrass requires very little nitrogen fertilizer, unlike other grasses used for hay/pasture. Only apply occasional light fertilization to established stands that show signs of nutrient deficiencies. Excess fertilization encourages weed competition.

What is the typical yield for switchgrass?

Yields vary considerably depending on variety, location and management. Productive lowland varieties in the South can produce 8-12 tons per acre. Upland varieties in the North may yield 3-5 tons per acre. Proper soil fertility and harvest management optimize biomass yields.

Does switchgrass have pest or disease problems?

Switchgrass is relatively free of serious pest and disease issues, especially when managed properly. Occasional issues may include leaf spot, rusts, smuts, aphids, armyworms or grasshoppers. Fields should be scouted periodically and treated only if outbreaks threaten stand health.

How do I control weeds in my switchgrass?

Weed management is critical during establishment when grass is vulnerable. Mow weeds early on, then use selective post-emergent herbicides for grassy weeds once established. Mowing and prescribed burning help control weeds in established stands.

Conclusion

Switchgrass is an excellent choice for biomass production, forage, and wildlife habitat. With proper variety selection for your region, suitable site preparation, timely planting, and conscientious maintenance, you can grow a thriving, productive stand of switchgrass. A small investment of time and effort up front will pay off for many years to come. Reap the rewards of this dynamic native grass with patience and attentive management.