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Q
I have been experimenting using recirculating flood and drain, maintained water temperature at 79°F,
pH of 5.5-6, and using the Douglas Peckenpaugh formulation, which is:
N=215 ppm, P=86, K=343, Mg=85, Ca=175, S=113, Fe=6.8, Zn=0.25, B=0.7, Mn=1.97, Cu=0.07, Mo=0.05
EC is about 2.0-2.5. My water went through reverse osmosis, with very low to no amounts of mineral. I grow
50-100 muskmelons. During the season, I only use this particular formula recipe from transplantation to fruiting
until harvest, but I see that once the fruit started to set, it seems the plants showed signs of potassium deficiency,
and the pH started to get on the lower side. It also looks like the plant is taking up a lot of water because the EC in
the nutrient reservoir went up at the end of the day. My question is: Do you have a suitable recipe for muskmelons
in different stages of development?
Ryan L.
A
Hello Ryan,
Fruiting plants such as muskmelons being grown on
this scale really do need to be provided with differ-
ent vegetative and fruiting nutritional formulations
as they move through the different growth stages.
Melons take up very high levels of potassium once
they have set fruit and this can rapidly deplete potas-
sium levels, particularly in a recirculating system.
It would be recommended to start the young plants,
right from seedling stage, on a balanced vegeta-
tive formulation, switch to a flowering/early fruit set
formulation as soon as the first small fruitlets have
set, then change again to a heavy fruit set formula-
tion as soon as the crop is in the rapid fruit expan-
sion stage. From then on, the nutrient recirculating
in the system should either be regularly analyzed
for all macro elements (N, P, K, Ca, Mg) to determine
if the fruiting formulation