Asparagus
Asparagus officinalis
Asparagus is a long-lived perennial (15-20 years productive life) that requires a permanent, well-prepared bed and patience - crowns should not be harvested in the first two years to allow the plant to establish strong roots. The reward is an annual spring harvest of tender spears over 6-8 weeks, earlier and better-flavoured than anything commercially available. Prepare the bed deeply with plenty of organic matter and choose a sunny, sheltered site.
Key facts
- Family
- Asparagaceae
- Category
- Leafy
- Sowing window
- Mar–Apr
- Sowing depth
- 50 mm
- Watering
- medium
- Frost sensitivity
- low
- Days to maturity
- 2-3 years from crowns before first significant harvest
- Harvest window
- Apr - Jun
Sowing notes
- -Plant 1-year crowns in March-April into well-prepared trenches
- -Do not harvest in the first 2 years - allow fern to develop and feed the crown
- -Productive for 15-20 years - choose the site carefully
- -Stop harvesting mid-June to allow fern to develop and restore crown energy
Varieties
Connover's Colossal is a traditional, well-established asparagus variety producing thick, well-flavoured spears with good consistency. It has been grown in UK gardens since the mid-19th century and remains popular for its reliability and classic asparagus flavour. An all-male F1 selection is now available for heavier yields.
Gijnlim is a Dutch-bred, all-male F1 asparagus variety widely regarded as one of the best for UK home gardens. It is early-cropping, high-yielding, and produces uniformly thick, well-flavoured spears with good resistance to rust disease. All-male plants do not set seed, which means more energy goes into producing spears.
Issues & threats
Wilting
EnvironmentalPlants are drooping or losing vigour. Most commonly caused by water stress but can also indicate root damage, vascular disease, or heat scorch. Identifying the cause quickly is important as some causes are serious.
Poor germination
EnvironmentalSeeds are emerging unevenly or not at all. Usually caused by soil temperature being too low, seeds sown too deep, poor seed-to-soil contact, or old seed stock.
Damping off
Fungal diseasePythium spp. / Phytophthora spp.
Young seedlings collapse at or just below soil level, caused by fungal pathogens that thrive in overwatered, poorly ventilated growing conditions. Can spread rapidly through a seed tray.
Yellowing leaves
EnvironmentalLeaves are turning yellow, which can indicate a range of problems including nutrient deficiency, overwatering, disease, or natural senescence. Identifying whether the pattern is upper or lower leaves, whole leaves or between veins, is key to diagnosis.
Stunted growth
EnvironmentalPlants are significantly smaller or slower to develop than expected. May be caused by poor soil, nutrient deficiency, root restriction, compaction, pest damage to roots, or disease.
Chewing damage
PestGeneral chewing damage from an unidentified pest, leaving holes or missing leaf sections. May be caused by caterpillars, beetles, or other insects. Inspect at dusk to identify the culprit.
Sap-sucking pests
PestGeneral sap-feeding pest activity causing weakened or distorted growth. May be caused by aphids, whitefly, scale insects, or other sucking insects. Inspect leaf undersides and growing tips to identify the pest.