Vertical Growing Strawberries in Stacked Pots (2025)
Project Status Update 11/28/2025
Project Status Update 11/22/2025
For the last of two weeks of October and the first 10 days of November we let volunteers at area food banks pick strawberries and raspberries for the area’s food panties.
I went into Walmart today and to my surprise there were no strawberries, very few raspberries, blueberries and blackberries. The berries they had were imported from Mexico. Has the lack of undocumented workers in California to harvest the berries finally have an impact on produce availability? We are still picking strawberries, see below. I just tested the berries for brix (sugar level) and they brix out with level of 15. In July the sugar level is 7.5. The berries have twice the sugar now as in July. Sugar water brix level is 24.
We believe a nutrient defiency is the reason for the multi-colored leaves. We are sending in soil sample and leaf tissue to Midwest Labs for analysis. We can add fish emulsion/seaweed to the drip irrigationtion to increate nutrients.
Berries 11.22.25
Project Status Update 11/20/2025
As of October 1, 2025, the SBIR/STTR program's authorization expired, causing a pause on new awards and delays in some solicitations. Our Phase 2 proposal recently submitted on Sept 22 2025 is on hold for evaluation by SBIR program reviewers.
Project Status Update 11/2/2025
The Fed gov’t review for VGSP proposal submitted proposal is on hold due to the gov’t shutdown.
Project Status Update 10/8/2025
We submitted a proposal on 9/22/25 for a USDA SBIR Phase 2 Grant ($594k). The proposal includes 3 other growers. Award anticipated Dec 2025 and project start date 4/1/26. But a delay is expected due to the current Federal government shutdown. Here are some of the documents submitted for your casual reading:
Commercialization Plan – Google Docs
Budget Justication VGSP 2025.xlsx – Google Sheets
Project Status Update: 9/9/2025
Here is a video of raised beds growing in between two rows of vertically stacked oval & round pots.
Vertical and raised bed grow Strawberries
On Monday, 9/9/2025, we picked 9 quarts from the vertical grow 2 – 4 stack (4 pots, 83 plants). The berry size was medium to large. 656 plants yield 9 quarts
On Monday, 9/9/2025. we picked 13 quarts from in ground high tunnel 6 beds 180 plants per bed. The berry size was small to medium. 1080 plants yield 13 quarts.
Within the last month the vertical grown strawberries have been increasing in yield whereas the in ground grown have been decreassing in yield.
Both the in ground and vertical systems are growing Monterey and Albion varieties,
GRANT Update: 7/16/2025
The USDA SBIR Phase 2 RFA came out. We are submitting a proposal due Sept 23 2025. We have three other growers invovled. We project the value of the proposal to be $600k.
GRANT Update: 2/1/2025
All Federal Scientific Research grants have been suspended indefinitely.
Presentaitons:
Presented at 2025 WI The Wisconsin Fresh Fruit and Vegetable Conference.Vertical Growing Strawberries in Stacked Pots (5)
We get our day-neutral strawberry plants from Lassen Canyon Nurseries from CA, Sweet Darling CA, Nourse MA, and Indiana Berries .
We planted 1200 plants (Albion and Monterey) on April 1 2025 in the ground in a 30×96 high tunnel and 1000 plants in 12 verticaly stacked pots, also in a high tunnel. Both were planted on the exact same day, with the first picking of vertical planting on May 9th and field grown on May 12th. We are recording yields for both.
Vertical Growing Strawberries in Stacked Pots (2024)
GRANT Update:
In 2017 we won a USDA SBIR Phase 1, titled “Vertically Growing Strawberries in Stacked Pots” $100k
In 2025 we will submit a USDA SBIR Phase 2. For additional info see below. $650k
PROJECT Update:
We plant strawberries in the field and vertically in stacked pots We planted our vertical stacked strawberries, late this year, at the end of May. We expect to harvest until the end of November. We have two rows (round & oval pots) of four stacks, four pots in each stack. The first row consists of round pots holding 25 gallons of substrate with 12 holes cut in the sides of the pots to accomodate one plant per hole. There is 20 plants per pot for a total of 80 plants per stack. The variety of day neutral stawberry is Portola. The substate is compost, potting soil, tiger 90, gypsum, mycorrhizal fungi. Each pot contains 1/4″ drip line watering twice daily for 4-6 minutes per cycle. We harvest Monday and Thursday with a goal of 2.5#s per plants. In pasts years we have achieved 2#s per plant. We are selling the berries at retail markets a $7.50 per quart/pound and wholesale at $6/pound. Most of our berries are sold retail.
Here is a video of the first row of stacked round pots:
Here is a video of the second row of stacked oval pots:
The oval pots hold 20 gallons of substrate, with no holes in the sides and 12 plants per pot for a total of 50 plants per stack.
The racking system holding the pot is made using lengths of 2×2 wood screwed together.
We plan to provide some heat to the tunnel in November/December in order to keep harvesting until Christmas. I addition, we might provide LED grow lites to promote growth and color. We have performed sugar test on the berries and they brix (measuremests of dissoled solids which includes the sugars) out at 14. Our berries brix out at 7.5 in July, 10 in Sept and 14 in November. Sugar water brix is 24.
Nov 28 2024. Due to unseasonably cold weather we decided to turn off the heat in the tunnel. We picked the berries:
The berries are white due to lack of heat (we kept the tunnel at 42F) and sun lite (thou we have LEDs, but not installed).
We plan to submit a proposal for a USDA SBIR Phase 2 grant($650k) for 2025 titled to Vertical Growing Strawberries in Stacked Pots. The USDA has a rule in order to surbmit a phase 2 proposal, the organization must have won a phase 1 grant. The proposal is due to be submitted in March 2025 and the grant awarded soon after. In 2016 Scenic Valley Farm won a phase 1 grant, $100k. The USDA indicates there is a 50% chance of winning the grant.
We are looking for 3-4 growers/university personnel to participate with us on this grant. If we win we will provide to each a 20’x30′ high tunnel, pots, racks, dripline and other irrigation supplies, controller(s), LED, heater, plants, substrates and labor funding. Participants are required to provide electricity and water. A list of tasks to be performed will be provided to partipants. The project will start in June of 2025 and run for two years. Progress will be presented in the Scenic Valley Farm (SVF) BLOG.
In 2022 at Scenic Valley Farm we will continue our multi year research & development of the VerticalGrowing Strawberries (VGS) in Stacked Pots project. The project will grow day neutral strawberries in large oval stock tanks (pots) stacked on one another via a rack. There will be 4 to 5 pots per stack with each pot holding 20-30 plants. The foot print of the stack is 3’x3′. In a field operation a 3’x3′ area, 9 plants can be planted. Using the VGS 80-100 plants can be planted per stack. With a typical high tunnel size of 30’x96′ we are looking to plant 6 rows of stacks, with 30 stacks per row, up to 18,000 plants per tunnel. In the ground you could plant, 1620 plants. The VGS will be located in a high tunnel (hoop house) in order to achieve a longer growing season and to simulate a California climate. Our goal per plant per year is 3 pounds. CA produces on the average 3#s per plant. Our day neutral strawberries growing in the VGS yield berries from the first week in May until the end of November. CA yield berries from end of February until the end of November. CA produces 90% of fresh berries consumed in the US or roughly 3 billion pound. We grow our strawberries in a substrate we produce composed of our aerobic and vermi compost, agricultural sulfur, calcium sulfate and mycorrhizal fungi.
All vertical growing systems that we are aware use hydroponic (water). Some of these use vertical pots, some use horizontal gutters/trough or some use a vertical PVC pipe system. Hydroponic systems use a growing medium like coco coir with water filled with nutrients. Our growing medium is mostly organic compost loaded with beneficial microbes and fungi. The microbes and fungi convert the organic matter to nutrients which are carried up the plant via the roots. In return the fungi receive carbohydrates via plant photosynthesis forming a symbiotic relationship between the plants and the fungi. Our soil substrate/organic matter grown strawberries have at least twice the brix level (sugar content) as hydropic grown strawberries, resulting in much better tasting. We have brix level scientific data supporting these conclusions and use a refractometer to measure the brix level.
Refractometer
The reading on a refractometer is the sum of all the solids in a sample. This includes sugar, carbohydrates, proteins, vitamins, minerals and everything else you can think of. However, the relative impact of any one chemical on the final reading depends very much on the amount of that chemical in the sample. The solids in strawberries are:
The nutrients in 3.5 ounces (100 grams) of raw strawberries (3Trusted Source) are:
- Calories: 32
- Water: 91%
- Protein: 0.7 grams
- Carbs: 7.7 grams
- Sugar: 4.9 grams
- Fiber: 2 grams
- Fat: 0.3 grams
Most of these berries’ carbs come from simple sugars — such as glucose, fructose, and sucrose — but they also contain a decent amount of fiber.
Brix Level of Field Grown Strawberries
Strawberries grown in our vertical stack pot growing medium have a brix level of 7.5 in July, 10 in September and 14 in November. We are attempting to acquire some hydroponic grown strawberries from Bushel Boy in Owantona MN to determine the brix level.
Here is a brief history of the past years R&D.
2016-2019 – We experimented with different pots/containers, different substrates, different strawberries (day neutral, short season (June)), different varieties (portala, monterey, san andreas, seascape, cabrillo, evie, albion, chandler, omaha), different racking methods, different methods of irrigation (drip tape, 1/4 tubing with emitters every 6″, pressure compensating emitters).
We looked at methods to cool the high tunnels. At temps above 85F the berries stop growing stop blossoming. We used our Environmental Management System (EMS) plc based controller to monitor/managed all high tunnel system and recorded daily temperatures. We found 1/2 days between June 1 and Oct 1 were above 85F.
We looked at and used shade cloths, exhaust and circulation fans, greenhouse evaporator coolers, water chilled coolers, circulating water and air cooled by our solar thermal heating/cooling system.
In Nov 2018 we received a USDA SBIR Phase 1 grant, Vertical Growing System Using Season Extending Technology, Temperature Control and Soil Based Substrates. The primary goal of the project was to research methods that more than double berry yields while increasing berry size. We researched and developed soil-based methods that increase plant densities compared to field cropping, resulting in a turnkey system that can be used by growers in the United States. The project compared traditional methods of high tunnel strawberry production in the region and hydroponic vertical methods in other regions to wholly novel vertical methods that use a soil-based medium. This vertical soil based production system allows locally grown strawberries to be available to both organic and conventional markets for seven months a year rather than one or two months. The grant lasted until the end of 2020.
Also in 2020 we attempted to improve berry production using LED lightning. We hung 5’ Philips LED production Module 2.2 150cm DRW LB HO. We tested these out in fall of 2020 to see if we could lengthen the growing season. We tested on the following racking system:
In 2022 we will expend to other racks to see if we can improve berry production on the bottom and sides where we have a limited amount of sun light.
During the entire R&D effort to determine the effective of feature implemented we picked the berries twice a week and recorded the results by stacks and plants in the stack. We recorded using the following Strawberry Pots Assignment form:
Using these results we could determine the berry yield by week/day/month/total season for each berry variety for each feature being tested. Information from this form we were able to determine yearly production increases in yields per plant. At the end of 2021 we stood at 2.3#s per plant. Our goal is 3#s per plant.
We have enclosed the high tunnel in insect netting to manage the Spotted Wing Drosophala (SWD) fruit fly from infecting and destroying the strawberry fruit. Up to 90% of the SWD can be controlled by the netting and the remaining controlled using the organic insecticide Entrust as needed. The SWD shows up middle to late July.
Starting in late August of every season the leaves of the strawberry plants would turn yellow, orange, and reds along with some remaining green. We called this the “Christmas tree” effect. Also the strawberry production during this cooler part of the season was not what we expected. We believed the reason was disease has set in due to the length of time the plants had been growing. In 2020 we told university researchers about the problem and the said it was probably a lack of nutrients. So in 2020 we did a leaf tissue analysis and found the plant was lacking nitrogen and potassium. The strawberry clusters were also drying out.
So in 2021 we replaced the the peat moss in the substrate with Tiger 90, which is high in sulfur and helped to decrease the substrate pH. Strawberry plants prefer a pH of 6-6.5. We we also told by a strawberry plant breeder in CA that strawberries don’t like peat moss. We increased the compost per cent in the substrate adding extra nutrition. So now our substrate consisted of our aerobic and vermi compost, agricultural sulfur, calcium sulfate and mycorrhizal fungi.
In 2021 we added dissolved oxygen to the irrigation water via a O2 Grow System. So stacks had the dissolved so we could monitor the effect.
To add additional nutrients in the late season we hooked a Dosatron injector to the irrigation system and injected a organic mixture of sea weed and fish emulsion, 3x4x3 NPK, also consisting of micronutrients.
The results in 2021 was an elimination of the “Christmas tree” effect, no more dried strawberry clusters and increased yield. At the end of 2021 we stood at 2.3#s per plant. Our goal is 3#s per plant.
In 2022 – Task: Can We Cool the High Tunnel
In 2022 we plan again to research cooling the summer temps in the high tunnel. We believe substantially cooling will increase the yields. We plan to continue where we lift off in 2019 using water chilled units,
open side walls, exhaust and circulations fans. Our mission is to eliminate as many 85F degree days as possible. We found 1/2 days between June 1 and Oct 1 were above 85F. The tunnel totally closed in the summer will heat to 130F. Strawberries stop growing, blossoming, ripening, producing when the temp is above 85F. You say how do we cool with the sidewalls open? Isn’t that like using a air conditioning unit in a house with windows open? With very limited test in 2019 during two days in September with above 85F we were able to lower the high tunnel temp by 3F using a single water chilled unit in a 30’x72′ high tunnel. The high tunnel has 6′ side walls that were rolled up, an exhaust fan and 4 recirculation fans. The chilled water cooler had 50F well water trickling through the unit. It, the exhaust fan and recirculation fans will be monitored and controlled by the Environmental Management System (EMS) plc controller and all set activate at 85F. We plan to add an additional water chiller.
For strawberries, we plan next week, 4/26, to plant 1100 day neutrals Cabrilla, Perfect, Precision & Osage strawberries in 23 vertical stacks racked with 82 -15 and 40 gal oval pots. 
The week of May 9th we planted 400 plants in two beds in a high tunnel. We plan to record the yields of these field grown strawberries to compare results we obtain from the VGS.
We will record the yield data using Strawberry Pots Assignment form. We have purchased all new irrigation line included some pressure compensating. Last year’s drip line was clogged. We plan to inject dissolve oxygen into the irrigation water using the O2 Grow System.
We have or plan to incorporate some of the things past years to improve production:
- We increased the compost per cent in the substrate adding extra nutrition. So now our substrate consisted of our aerobic and vermi compost, agricultural sulfur, calcium sulfate and mycorrhizal fungi. This provides additional end of the season nutrition along with adding organic seaweed and fish emulsion to the irrigation water via the Dosatron. We need to filter this irrigation water with a fine inline filter to eliminate particles that will clog the dripline emitters.
We might look at our Solar Thermal to heat the tunnel in the Spring and Fall and reverse the air flow to use the thermal cooling qualities of the ground to cool the tunnel in the Summer.
CALIFORNIA DROUGHT updated 4/22/22
California grows 90% of the fresh strawberries or 3 billion strawberries for the US. The drought in California is affecting ag with thousands acres of farmland going fallow. The drought is starting to affect strawberry production.
With California entering the third year of severe drought, federal officials said Wednesday they won’t deliver any water to farmers in the state’s major agricultural region — a decision that will force many to plant fewer crops in the fertile soil that yields the bulk of the nation’s fruits, nuts and vegetables.
“It’s devastating to the agricultural economy and to those people that rely on it,” said Ernest Conant, regional director for the U.S. Bureau of Reclamation. “But unfortunately we can’t make it rain.”
The federal government operates the Central Valley Project in California, a complex system of dams, reservoirs and canals. It’s one of two major water systems the state relies on for agriculture, drinking water, and the environment. The other system is run by the state government.
In previous years the federal and state government have provide 10% of water supply for ag. In 2022 that government supply has been cut back to zero.
Feds won’t give water to California farmers due to severe drought
Newsom’s drought order aims to slow Ag well drilling 4.3.22
New wells for agriculture will be more difficult to drill in the San Joaquin Valley under Gov. Gavin Newsom’s recent executive order in response to the ongoing drought.
Part of the order prohibits new wells from being drilled without approval from local groundwater sustainability agencies (GSA) first. The GSAs must determine that new wells or changes to existing wells won’t hurt their groundwater sustainability goals, damage infrastructure or cause ground subsidence.
“It’s a historic move that we’re really proud to see happening,” said Kyle Jones, policy and legal director for nonprofit Community Water Center.
Most emergency drought actions from governors in the past have focused on urban water conservation, said Jones.
Southern Nevada Water Authority’s original water intake valve in Lake Mead — in service since 1971 — is now visible above the water line.
Lake Mead plummets to unprecedented low, exposing original 1971 water intake valve
Sweeping water restrictions will change life in Southern California: A guide
The Plan:
On Tuesday, May 3rd 2022, the Metropolitan Water District ordered outdoor water usage be restricted to just one day a week for about 6 million people in parts of Los Angeles, Ventura and San Bernardino counties. The restrictions will take effect June 1 and will apply to areas that depend on water from the drought-ravaged State Water Project.
Officials worry Southern California won’t have enough water to get through summer without unprecedented cuts
May 7 2022
The two largest reservoirs in California are already at ‘critically low levels’ and the dry season is just starting
“We anticipate in 2022 that in the Sacramento Valley alone, over 350,000 acres of farmland will be fallowed,”