Organic Hydroponic Lettuce

Our organic hydroponic lettuce was developed in 2015 at the request of hotel chefs who wanted consistent heads all year round, including through the long rainy months in the Central Highlands. It is grown in our Cau Dat sourcing area, where Thalvora has operated a 14-hectare greenhouse cluster since 2006.

Greenhouse growing

Seedlings are raised in coir plugs for 14 days before moving into recirculating hydroponic channels. The nutrient solution uses only inputs permitted under EU organic rules, with conductivity and pH checked twice a day. Shade netting and extraction fans hold greenhouse temperatures at 18–24 °C without electric heating.

• Three main varieties: Romaine, green butterhead and red lollo.
• A growing cycle of 32 to 38 days depending on season, with around 55,000 heads harvested each week.
• Recirculated water is filtered and reused, saving around 85% of the water needed for soil-grown lettuce.
• Pests are managed with insect netting, coloured sticky traps and beneficial insects, with no chemical insecticides.

Harvesting and packing

Heads are lifted from the channels with their roots and part of the growing plug intact, so the leaves keep drawing moisture and wilt more slowly. Packing takes place in a facility inside the greenhouse site:

• Trimming: damaged outer leaves are removed, leaving heads of 180–220 g.
• Rapid cooling: 40 minutes in a 2 °C cold room immediately after harvest.
• Bagging: each head goes into an open-top sleeve, packed 20 to a ventilated case.
• Labelling: a QR label records harvest date, greenhouse block and nutrient batch.

Food safety

The greenhouse site is certified to EU Organic and GlobalG.A.P. and is re-audited every year by an independent certification body. Incoming water is tested weekly for microbiology, and recirculated solution passes through UV sterilisation before returning to the channels. Every outbound lot receives a sensory check and rapid microbiological screening before loading.

Storage and delivery

Lettuce travels chilled at 2–4 °C, reaching Ho Chi Minh City the same day and Hanoi or Da Nang within 24 to 30 hours. Because the roots stay on, shelf life reaches 10 days, about three days longer than cut-root lettuce. Foodservice customers receive fixed deliveries three times a week, and volumes can be adjusted to a hotel's occupancy forecast.

For professional kitchens

Romaine has firm, crunchy leaves suited to Caesar salad or a quick turn on the grill. Butterhead is soft and sweet, ideal for lettuce wraps and plate liners. Red lollo adds colour to buffets and starters. To keep the leaves crisp, trim the roots only just before preparation and refresh the leaves in cold water for five minutes before serving.

Traceability

Scanning the QR code on the sleeve shows the greenhouse block, sowing date, harvest date and test results for that lot. Hotel purchasing teams also use this information to keep supplier records for food safety audits. Twice a year, Thalvora invites the kitchen teams of its foodservice customers to the Cau Dat greenhouses to see growing and packing first-hand.