Why does asparagus require multiple years before harvesting?
Written by
Julia Anderson
Reviewed by
Prof. Samuel Fitzgerald, Ph.D.Asparagus requires a 2-3 year wait before harvesting; this time is needed for strong perennial roots to grow, and for the crowns to build energy in preparation for producing spears. I've seen eager gardeners harvest a few spears prematurely, only to lose their entire crop. Your patience will provide the foundation for you to enjoy spears every spring for many years to come.
During the first 1-2 years of growth, the plant is expending energy on rooting out rather than spreading out. In the plant's crown, rhizomes develop as the primary storage organ, storing carbohydrates. It is from these stores that the plant will rapidly push a spear through the soil in the spring. If this energy were not painstakingly stored, the plant would dilute itself and die off early.
Year 1
- Root Expansion: Develops 12-18 inch deep root system
- Energy Focus: Stores carbohydrates in rhizomes
- Fern Growth: Produces photosynthetic foliage only
- Zero Harvest: No spear collection allowed
Year 2
- Rhizome Growth: Doubles energy storage capacity
- Bud Formation: Creates multiple spear-producing buds
- Fern Maturity: Grows 5-6 foot tall ferns
- Maintenance: Weeding and watering only
Year 3
- First Harvest: Limited 6-week collection period
- Energy Reserves: Sufficient for spear production
- Establishment: Root mass supports future growth
- Yield Limit: Harvest only pencil-thick spears
Harvesting too soon robs plants of vital energy. The spears are pulled, and the carbohydrates that should have gone into the roots are drained from the plants. This weakens the crowns and renders them helpless to resist disease. I mark my calendar to enforce the waiting period, and I expect the harvest to be all the sweeter for the discipline.
Maximize root growth during waiting years. Apply ample balanced fertilizer in early spring, just before ferns reemerge. Do not allow the soil to dry out completely, but avoid allowing it to become waterlogged. Weed thoroughly within 8 inches of each crown. All these practices enhance our good energy storage systems.
In the third year, you will only harvest pencil-thick spears for six weeks. This limited harvest will draw on the plant's vitality, but not sufficiently to harm it. By the fourth year, you should be picking for a full eight-week period. I weigh spear diameters daily throughout the first harvest.
The wait is worth the reward: well tended beds can produce for decades with little maintenance. Each spring they provide you with sweet tender spears earlier than any store bought variety. That first home grown meal makes the wait all worth it!
Read the full article: When to Plant Asparagus: Essential Growing Guide
