Strawberry

Everbearing Strawberries.

Fruit across a long window rather than a single flush.

Grow strawberries under glass The numbers

Ripe fruit, week after week

An everbearing crop is picked continuously rather than in one burst, and that changes what a local grower can promise. Ripe strawberry has a short life and cannot be stored to cover a gap. Supply has to arrive at the rate it is eaten, or the shelf gets filled from somewhere further away.

A plant that keeps flowering solves that. It puts fruit into the market in a steady rhythm across a long window, so the same short journey applies every week rather than only in the peak. Vitamin C, sugar and aroma are all highest in fruit that ripened on the plant, and a continuous crop makes ripe picking the ordinary case instead of the lucky one.

The window is where the value sits. Fruit grown under glass near its market covers the shoulders of the season, when the alternative on the shelf has travelled a long way and was picked accordingly. Continuity is not only a commercial argument. It is what keeps the fruit on offer at the quality the crop is capable of.

Nutrition facts

Strawberries, raw

Per 100 g

Energy: 32 kcal
Fat: 0.3 g
Carbohydrate: 7.68 g
Sugars: 4.89 g
Fiber: 2 g
Protein: 0.67 g
Sodium: 1 mg
Potassium: 153 mg
Vitamin C: 58.8 mg

Source: USDA FoodData Central, FDC 167762

Everbearing strawberry flowers and fruits repeatedly rather than in one short burst, which is what lets a glasshouse crop supply a market continuously instead of for a few weeks. It is the basis of the Dutch fresh crop under glass, and the extended picking window is the commercial reason to grow it under protection at all.

What the crop needs

The crop is grown on suspended substrate gutters at working height, with drip irrigation and drain recirculation. The root zone is small relative to the fruit load, so water and salt management do most of the work of holding quality, and the crop is sensitive to interruptions while fruit is filling. Picking at height is what keeps the labour sustainable across a long season.

What the greenhouse has to do

Strawberry under glass is grown on suspended gutters, and that choice runs through the whole building. Picking happens at waist height instead of ground level, which changes the labour plan more than any other decision on the crop; the gutters have to be hung from the structure, so the load path is designed in from the start rather than added to a finished house.

A long picking window is what the house is paid for. Quality has to hold from the first flush to the last, which puts the weight on climate stability rather than on peak performance — screening and heating that keep the plant productive through the shoulders of the season, ventilation that keeps the canopy dry, and irrigation with the buffer to carry a fruiting crop through hot weeks.

DutchGreenhouses® specifies the structure, climate, screening and irrigation around the strawberry crop, its picking window and the local climate, so quality holds across the whole period rather than the first flush. Get in touch to plan a strawberry greenhouse.

Crop data Everbearing strawberries

Day climate^1,2,3

Air temperature: 15–20 °C
Relative humidity: 68–75 %
Daily light integral: 8.3–14.3 mol/m²/d
Photoperiod: 14–18 h
CO₂ concentration: 500–900 ppm

Sources (3)

Kas als Energiebron / WUR, 2021, project 20145 — Fresh everbearers in source–sink balance E056
WUR, 2023, WPR-1216 — Fossil-free strawberry scenarios E057
Kas als Energiebron / Plant Lighting, 2024, LED report V — LED spectrum, photoperiod and water response E059

Reference values, not a specification. Setpoints are calculated per greenhouse, crop and location.

Questions

Everbearing strawberry, asked and answered

Why grow strawberry on suspended gutters?

Picking at waist height instead of ground level, and a root zone that can be controlled. The gutters hang from the structure, so the load path belongs in the design of the house rather than in a later fit-out.

What does a long picking window ask of the greenhouse?

Stability rather than peak capacity. Quality has to hold from the first flush to the last, so screening, heating and ventilation are specified for the shoulders of the season, not for its best weeks.

What limits fruit quality late in the picking window?

Plant condition and climate control through the warm months. A canopy that stays wet or a root zone that swings shows up in the fruit that is picked weeks later.