Hemp Growing Cycle: A General Guide

Hemp (Cannabis sativa L.) is a versatile crop grown for its fiber, seeds, and cannabinoid-rich flowers. The growing cycle generally follows four main stages, though specific timing can vary based on cultivar, climate, and intended use (e.g., fiber vs. CBD).

1. Propagation Stage (Seedling to Early Vegetation)

This stage focuses on establishing healthy, robust plants.

• Timeline: Approximately 3 to 6 weeks.
• Key Activities:
  • Sourcing: Obtain certified industrial hemp seeds or clones (for female-only crops).
  • Germination: Seeds are started indoors or directly sown into the field after the last expected frost.
  • Transplanting: If started indoors, seedlings are moved to the field once they have developed a few sets of true leaves and the outdoor conditions are favorable.
• Conditions: Requires warm soil temperatures and moderate, consistent watering.

2. Vegetative Stage

The plant's primary focus is on producing large amounts of foliage and structural growth, increasing its overall size.

• Timeline: Approximately 6 to 10 weeks, depending on the desired plant size and day length (hemp is a photoperiod-sensitive plant).
• Key Activities:
  • Rapid Growth: The plant dedicates energy to growing stems, branches, and leaves.
  • Nutrient Uptake: High demand for Nitrogen (N) is crucial during this phase to support aggressive growth.
  • Training/Pruning: For flower/CBD production, some growers prune to encourage bushier growth and more flower sites.

3. Flowering Stage (Reproductive Phase)

The plant shifts its energy from growth to flower (bud) production. This stage is critical for cannabinoid and seed development.

• Timeline: Approximately 5 to 9 weeks.
• Key Activities:
  • Flower Initiation: Triggered by the change in daylight hours (shorter days).
  • Sexing: Growers for CBD/cannabinoids must remove all male plants early in this phase to prevent pollination, which significantly reduces flower potency and quality.
  • Nutrient Shift: Nutrient demand shifts from Nitrogen (N) to Phosphorus (P) and Potassium (K) to support flower development.
• Conditions: Requires lower humidity and consistent temperatures to prevent mold and mildew.

4. Harvest and Post-Harvest

Harvest timing is determined by the intended end-product (fiber, grain, or flower/CBD).

Fiber/Grain Harvest

End-Product	Harvest Timing	Typical Method
Grain (Seed)	When 60–70% of seeds are mature	Combine harvester, similar to wheat
Fiber (Stalk)	Before flowering or during early seed set (depending on fiber quality)	Special machinery or conventional hay/silage equipment

CBD/Flower Harvest

This is the most labor-intensive harvest, typically occurring when cannabinoid levels are at their peak.

• Timing: Determined by trichome development (small, crystal-like glands on the flower) and desired maturity.
• Drying: Flowers are carefully cut and hung to dry slowly in a controlled environment to preserve terpenes and cannabinoids.
• Curing: A post-drying process that enhances flavor and quality.