What are common mistakes in asparagus harvesting?
Written by
Julia Anderson
Reviewed by
Prof. Samuel Fitzgerald, Ph.D.Mistakes in harvesting are the most serious of all with asparagus crops, shortening the life of a bed and lessening yields. Cutting small spears leads to weakened crowns. Harvesting in wet weather can distribute fungal diseases. I have known beds to fail in the third season due to overharvesting on a daily basis. How you handle your crop will determine the success of your asparagus!
Premature Cutting
- Spears thinner than pencils: Lack energy reserves
- Impact: Reduces next year's yield by 40%
- Sign: White instead of green stems
- Solution: Measure diameter before cutting
Weather Misjudgment
- Wet harvests: Spread rust spores on tools
- Heat stress: Above 85°F exhausts crowns
- Impact: Increases disease transmission
- Solution: Harvest only dry cool mornings
Overharvesting
- Taking >50% daily spears: Depletes carbohydrates
- Extended seasons: Beyond 8 weeks
- Impact: Crown starvation and decline
- Solution: Limit to 2-3 spears per plant daily
Tool sanitation. Cleanse knives between each plant with 70 percent alcohol. I pack several knives and constantly rotate to a fresh 'cold' knife. My kitchen knives are colour-banded for the different bed sections. This simple habit prevents a scourge wipe-out by Fusarium of entire plantings.
Time your harvests for the first thing in the morning, when the spears are crispest. Do not cut in the afternoon, when plants are stressed. Stop completely when the temperature reaches or exceeds 85°F, as a heat wave descends. I like to monitor my soil at the level of my soil crowns. Even cutting in the heat of the day will typically bang up those energy storage cells permanently.
That said, limit the harvest to 8 weeks maximum, even if the spears stay healthy, and mark the start date on a calendar to remind you when to quit. I always stop when 30% of the spears look spindly y. I leave 5-6 ferns on each plant so it can rebuild its reserve. Sticking to it assures us of an abundant harvest next year!
Train your new harvesters using some demonstration beds. Show them the pencil-thin spears, or thicker ones, versus the immature ones. Practice snapping the proper way, i.e., above the soil. I have been having workshops in the spring, applying what I have preached. I have been teaching restraint. Properly harvesting your beds will return your investment for decades of spring harvests.
Read the full article: When to Plant Asparagus: Essential Growing Guide
