How to Grow Pencil Flower
Wikimedia Commons
Pencil Flower
Stylosanthes guianensis
herbStylosanthes guianensis, commonly known as pencil flower or Brazilian stylo, is a tropical legume grown primarily as a forage and cover crop. This nitrogen-fixing plant produces small yellow flowers and thrives in warm climates, making it valuable for pasture improvement and soil enrichment. It is drought-tolerant and adaptable to poor soils, particularly in tropical and subtropical regions.
When should you plant Pencil Flower in your zone?
Get a personalized planting timeline — when to start seeds, transplant, and harvest — based on your USDA zone and local frost dates. Free to start.
Example Pencil Flower timeline · Pittsburgh, PA (Zone 6b)
-
Plant Pencil Flower
Around Apr 17Near Pittsburgh's average last spring frost.
-
Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
-
Harvest Pencil Flower
Around Jul 16≈ 90 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Pencil Flower dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 9b-12, best suited for tropical and subtropical climates
Sign up free to see if Pencil Flower grows in your zone — and get a personalized planting timeline.
Get my Pencil Flower timeline →Growth Stages
Germination & Seedling
2-3 weeksSeeds germinate in 7-14 days. Seedlings develop small compound leaves and a thin taproot system.
Keep soil consistently moist but not waterlogged. Ensure adequate light. Thin seedlings to proper spacing. Inoculate soil if planting in new areas.
Vegetative Growth
4-8 weeksPlant establishes and develops multiple branches with small pinnate leaflets. Strong taproot develops, reaching deep into soil layers.
Water moderately during dry periods. Allow soil to dry between waterings. Minimal fertilization needed due to nitrogen fixation. Monitor for pests.
Flowering
4-6 weeksSmall yellow flowers appear in compact axillary inflorescences along stems. Flowering occurs in clusters and continues over several weeks.
Maintain consistent moisture without overwatering. This is the critical period for pollinator activity. Avoid heavy nitrogen fertilization which may reduce flowering.
Seed Development & Maturation
4-6 weeksFlowers develop into small legume pods containing 1-2 seeds. Pods mature from green to brown, becoming hard and dry.
Reduce watering as seeds develop. Allow plants to dry on the stalk before harvest if collecting seed. Pods may be prickly or have awns.
Post-Harvest/Regrowth
Continuous with proper managementAfter cutting for forage, plant recovers with vigorous regrowth from remaining root system and basal buds.
Allow adequate recovery time (4-6 weeks) between harvests. Don't cut lower than 2-4 inches to maintain plant vigor. Irrigation aids regrowth.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
-
Select resistant varieties; improve air circulation; avoid overhead irrigation in humid conditions; apply copper-based fungicides if severe
-
Remove affected leaves; reduce humidity through spacing; fungicide applications in severe cases
-
Monitor for frothy masses on stems; natural predators often provide control; severe infestations may require insecticidal soap
-
Practice crop rotation; use resistant varieties where available; maintain soil health with organic matter
-
and
(Acrididae family)
Monitor populations; hand-picking for small infestations; insecticides if causing significant damage
Uses
Livestock Forage
CulinaryPencil flower is widely used as green manure and improved pasture for cattle, goats, and sheep in tropical regions. It provides high-quality, protein-rich forage that improves livestock nutrition and herd productivity. [source]
Soil Improvement & Cover Crop
HouseholdAs a nitrogen-fixing legume, Stylosanthes guianensis enriches soil through its symbiotic relationship with Rhizobium bacteria, reducing need for synthetic nitrogen fertilizers. It is commonly used as a cover crop to restore degraded soils and improve soil structure. [source]
Traditional Use
MedicinalIn some traditional medicine systems, particularly in South America, various Stylosanthes species are used to support health and vitality. Contains bioactive compounds including flavonoids and other phytochemicals. [source]
Pollinator Support & Biodiversity
WildlifeThe yellow flowers attract native bees and other pollinators, supporting pollinator populations in agricultural and tropical landscapes. The plant also provides habitat and food resources for various insects. [source]
Agroforestry Systems
CraftUsed in tropical agroforestry systems for erosion control, slope stabilization, and as an intercrop in mixed farming systems. Its deep taproot system helps improve soil structure in degraded lands. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
For forage use, cut when plants reach 12-18 inches tall or at early flower stage for best nutritional value (10-15% crude protein). Multiple harvests possible per year with adequate moisture. For seed collection, allow pods to fully mature and dry on plant, then thresh and clean. Best seed quality when harvested at 100% pod maturity.
Fun Facts
- 🌱 Stylosanthes guianensis is native to South America and has become one of the most widely used tropical forage legumes globally, particularly in Africa, Asia, and Australia.
- 🌱 The plant's name 'Pencil Flower' comes from its thin, pencil-like stems, and 'Brazilian stylo' references its importance in Brazilian pasture and rangeland management.
- 🌱 A single Stylosanthes plant can fix 100-300 kg of nitrogen per hectare per year through its relationship with Rhizobium bacteria, making it highly valuable for sustainable agriculture in nitrogen-poor tropical soils.
Gardening Terms
New to gardening? Learn about terms used in this guide:
Join 30,000 gardeners planning their gardens with LizPlants.
Get your personalized Pencil Flower planting timeline
Tell us your zip code and we'll calculate exactly when to start Pencil Flower seeds, transplant seedlings, and harvest — based on your USDA zone and local frost dates. Includes calendar reminders and printable task lists. Free to start.
Get my Pencil Flower timeline →