How to Grow Aggregatum
Aggregatum
Allium aggregatum
vegetableAggregatum, also known as shallot or Asian shallot, is a small bulbous plant in the onion family that produces clusters of elongated bulbs with copper-red or purple skin. It has a milder, slightly sweet flavor compared to regular onions and is prized in Asian and European cuisines. The plant grows compact foliage and is relatively easy to cultivate in most temperate climates.
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Example Aggregatum timeline · Pittsburgh, PA (Zone 6b)
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Plant Aggregatum
Around Apr 17Near Pittsburgh's average last spring frost.
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Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
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Harvest Aggregatum
Around Jul 16≈ 90 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Aggregatum dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 3-9, with best performance in zones 5-8
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Get my Aggregatum timeline →Growth Stages
Sprouting
1-2 weeksSmall green shoots emerge 1-2 weeks after planting; root system begins developing below soil
Ensure consistent moisture; keep soil at 50-60°F for optimal sprouting; thin weak seedlings if direct sown from seed
Vegetative Growth
4-6 weeksPlant develops 3-5 slender, tubular leaves; foliage grows upright reaching 8-12 inches tall
Maintain consistent moisture and full sun exposure; apply balanced fertilizer every 3-4 weeks; keep weeds controlled
Bulb Formation
4-8 weeksFoliage thickens slightly; underground bulb clusters begin to swell and develop individual segments
Reduce nitrogen fertilizer; increase potassium to promote bulb size; maintain steady watering without waterlogging
Maturation
2-3 weeksFoliage yellows and begins to dry down; bulb skin hardens and becomes papery; cluster bulbs reach full size
Gradually reduce watering as foliage dries; stop watering 2 weeks before harvest when tops fully yellow; do not fertilize
Harvest & Curing
2-3 weeks curing after harvestFoliage is completely brown and dry; bulbs are firm with dry, papery skin; ready for lifting and storage
Harvest when 75% of tops have fallen over; cure in warm, dry location for 2-3 weeks before storage; trim dried tops and roots
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Use row covers over young plants; remove infested bulbs; practice crop rotation; apply spinosad or neem oil if needed
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Spray with insecticidal soap or neem oil; maintain adequate moisture; remove heavily infested leaves; encourage beneficial insects
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Use floating row covers; apply diatomaceous earth around base; practice 3-year crop rotation; avoid overwatering
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Ensure good air circulation; avoid overhead watering; remove infected leaves; apply copper fungicide if severe
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Plant disease-resistant varieties; avoid waterlogging; practice crop rotation; remove infected plants immediately
Uses
Aromatic cooking ingredient
CulinaryAggregatum bulbs have a mild, sweet onion flavor with subtle garlic notes, making them ideal for soups, stir-fries, sauces, and Asian dishes. The delicate flavor complements French shallot preparations and is a key ingredient in vinaigrettes and Southeast Asian pastes. [source]
Fresh or pickled preparation
CulinaryYoung aggregatum bulbs can be pickled whole for condiments, or used fresh in salads and raw preparations. The tender texture and mild taste make them suitable for delicate culinary applications. [source]
Traditional digestive and immune support
MedicinalLike other Allium species, aggregatum contains compounds with potential digestive and immune-supporting properties, used in traditional Asian medicine for overall wellness. [source]
Seed production and propagation
HouseholdAggregatum is grown commercially and by home gardeners for seed production, as bulblets naturally propagate when stored, allowing continuous replanting without purchasing new sets. [source]
Pollinator-friendly flowering
WildlifeIf allowed to bolt, aggregatum produces delicate lavender-pink flower clusters that attract pollinators and beneficial insects to the garden ecosystem. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Harvest when foliage has completely dried and turned brown, typically 90-120 days after planting. Gently loosen soil and pull up clusters; shake off excess soil. Cure bulbs in a warm (70-80°F), dry, well-ventilated location for 2-3 weeks before storage. Store in mesh bags in a cool (50-60°F), dark place; can last 6-8 months. For fresh use, harvest immature bulbs earlier and use immediately.
Fun Facts
- 🌱 Aggregatum is also called 'Asian shallot' or 'Chinese shallot' and has been cultivated in Southeast Asia for centuries before spreading to European gardens.
- 🌱 Unlike common shallots that form single bulbs, aggregatum naturally produces clusters of 6-10 smaller bulbs from a single planted bulblet, making it highly productive in limited space.
- 🌱 The plant is particularly valued in Southeast Asian cuisine, especially in Vietnam, Thailand, and Indonesia, where it forms a culinary trinity with garlic and chili.
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