Giant pumpkin

Plant type: 

Atlantic Giant Pumpkin (this one is named “Rae of Hope”).

Application method: 

On 25 June 2023, material was spread on the surface of 55 sq ft out of a 600 sq ft pumpkin patch (9.2%), then tilled into the soil. (photo 1)

Location: 

A grower from Los Altos, Ca who competes in the annual world championship of giant pumpkins, held in Half Moon Bay, California.

Results: 

We added our soil amendments into a pumpkin patch which was already planted with two pumpkins. One plant was farmed conventionally, planted 2 days earlier. The other plant received our soil amendments. The first “measurement/observation” occurred on July 8, 2023. After 12 days, the vines (and leaves) growing in the treated soil grew 160% faster than the vines grown in untreated soil; there were no pumpkins yet. 

The next checkpoint was Aug 6, 2023. The pumpkin planted earlier weighed 350 lbs and the treated pumpkin weighed 300 lbs - exactly as expected, as at this time they add 25 lbs/day.   This grower is aware that his soil contains a pathogen which attacks the plant roots. At day 40, he had to chop off the main vine of the treated plant to prevent rot from spreading into the pumpkin. To the grower’s surprise it continued to grow, supplied only by “side vines”. 8 days later, the same rot forced him to chop off the main vine to the untreated pumpkin.  By this time, the treated plant outweighed its older sibling.  The untreated plant has stopped growing, also only supplied by its side vines. Photo 2 below was taken on 24 Sept ’23; our “Rae of Hope” is 38” tall, 59” wide, and weighs 1200 lbs. It will be entered at the Half Moon Bay Pumpkin Festival competition on  Oct 9, 2023; we’ll report the final weight then.

With only two plants in this study, one treated and one not, and only 9% of the patch treated, these results are “promising” but not “conclusive”. This field trial merits expansion in 2024. 

Photo 1: Soil amendments added June 27, 2023.   

Photo 2: 1200 lb pumpkin, Sept 24, 2023.