Cucumbers Are BIG MONEY When Grown in Portable Farms
by Colle and Phyllis Davis
If cucumbers grown in a Portable Farms™ Aquaponics Systems are planted, raised and sold as ‘organic,’ the grower can receive higher prices based on their organic origins further reducing the ROI than stated in this article.
Cucumber production begins 60 to 70 days after seeding. For good production, a temperature range of 75 degrees to 80 degrees F during the day is desirable. While peak daytime temperatures of 85 degrees to 95 degrees F are tolerable, prolonged periods of high temperatures may adversely affect fruit quality. Night temperatures no lower than 65 degrees F will allow a rapid growth rate and earliest fruit production. At 55 degrees to 60 degrees F, savings in fuel costs will be significant, but growth rate will be slower and harvest will be delayed.
Fruit generally grows to market maturity 12 to 15 days after the flower opens.
Considering these variables, yields range from 1 – 1 ½ to 3 pounds of fruit per plant per week, during mid-harvest on an umbrella trained crop. Twenty to twenty-five fruit may be expected over a 10 to 12 week harvest period.
Cucumber production from a single full size 5′ x 40′ (200sq ft) [1.5m x 12m (18m2) Grow Tray:
- Each Grow Tray can hold 106 plants 18in x 12in (45cm x 30cm) centers and are planted twice a year
- Production is normally over a 10 to 12 week period
- Because the plants spread out so much they need to be trained in a V shape or directly vertical
- Plants may require some pruning
- The staking or trellising can be installed permanently
- Cucumbers yield is between 1.5 and 3 lbs [0.7 and 1.3k] per plant per week depending on variety
- Yield per plant is 20 to 25 cucumbers per plant depending on variety
- No pesticides, fungicides or artificial fertilizers are ever used
- Cucumbers can be harvested and used the same day for peak flavor and texture plus they store well
- Yields 4,000 lbs to 4,500 lbs [1,800 to 2045kg] per year per Grow Tray
- 85lbs [38kg] per week
- 11.7lbs [5kg] per day
Each Module contains one Grow Tray, one Fish Tank and one Clarifier. The components to make the Module functional also include a special pump and valve system, a control panel, air pumps and related hardware and wiring.
Each Module cost approximately US$4,000 completely installed (Southern California retail cost), outside the US and Canada the price is approximately half that amount. The Modules must be housed in a climatically adapted structure/greenhouse with a translucent or transparent waterproof roof and walls and one or more thermostatically controlled exhaust fans. In the tropics the sidewalls can be screen or netting and the exhaust fans will still be needed.
Using the lowest yield with the shortest harvest season and three crops per space per year the Return On Investment will be approximately 8 months [85 lbs (38kg) x 52 weeks = 4,220 lbs (1,900kg) of cucumbers per year per module] and priced at $2.25 per pound = US$9,945]. In most cases this production number will be much higher and will continue to rise as the operators become more skilled and the system matures.
Labor costs are higher than with lettuce because of the training and harvesting of cucumbers. This is true for tomatoes, zucchini, peppers and any plant that requires extra time after planting. Lettuces does not, plant it and then a few weeks later harvest it and plant the same place again. One person can operate a 10,000 sq ft PFAS if they are only growing lettuce. With other bush or vine crops two to four additional personnel are required.
Please note: The above numbers are based on the lowest expected yields from greenhouse grown crops, use the shortest possible harvest time plus the longest time from transplant to finish harvest. In other words, the lowest possible output from the Module for this crop is shown. The actual output from each Module can and probably will be from two to four times as high resulting in a much shorter ROI.