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Saco, Maine

hi - has anyone had a plant experience molybdenum deficiency? if so, how did you treat it?

thanks,
chuck

7/26/2002 7:14:03 PM

derry n.h u.s.a.

chuck: if you used Cow manure,it should have all the micro elements that any plant would need,if you use Peters fertilizers I.E,20-20-20 that would have all the micros a plant would need also,What are the symptoms??
Yellowing leafs on the older leafs would be nitrogin
yellowing streaks in new growth would most likely be Iron deprived,Ihave no idea what
a Molybendom deficent plant would look like.More info.Hope this helped somewhat!:)John G

7/26/2002 8:51:14 PM

Sask, Canada

Chuck:

Molybdenum (mo lib den um) is a trace mineral necessary for plants.

Molybdenum deficiency is rare in plants as only small amounts are needed. This type of deficiency first shows up in young leaves and shows up as a dying area around the leaf edges.

Molybdenum deficiency shows up first in acidic type soil, water and growing mediums. Such as a peat moss medium.

Molybdenum is needed in trace amounts. It acts as an electron carrier in converting nitrate (NO3-) or ammonium(NH4+). This means it is important in allowing plants to use the nitrogen in the nutrients it takes in.

A molybdenum deficiency looks like nitrogen starvation as it reduces the plants ability to utilize nitrogen. Edges of the leaves curl up and die to a brown color, there is some brown discoloration of the leaf edges. Yellow and orange spots start to appear on the outside margin of the leaves. It first effects the older lower leaves.

There is also what is known as whiptail - a condition caused by molybdenum deficiency where the plant leaf does not fill out, and the leaf midrib grows long and twisted like a whip. It is often seen first on the shaded portion of the plant.


To fix the problem:

Apply a foliar spray made of 1 ounce of sodium or ammonium molybdenate in 100 gallons of water. Phosphate fertilizers usually have enough molybdenum as an impurity to act as a molybdenum supplement for soil or nutrient water.

Hoped this Helped
TTYL
Ernie
Giant Veggies

7/26/2002 9:47:29 PM

Sask, Canada

Oh almost forgot,

Sodium molybdenate can usually be purchased from an Ag store like farm co-op or some type of farm ag outlet.

Ammonium molybdenate can be purchased from a chemical company or someone in a lawn type business as they use it in turf's and the like's (ie. golf courses)

TTYL
Ernie
Giant Veggies

7/26/2002 10:47:14 PM

Saco, Maine

Thank you Giant Veggies and John G for your help! I'm now not 100% certain that my problem is molybdenum deficiency, but it sure sounds like it. Symptoms are dry, brown leaves, mostly the older ones and lack of lush greenness in the vine. Also, the whiptail appears to be happening also.
I believe I made the mistake of planting my plant in a mound of 1 year old composted cow manure. I hadn't mixed in any loam, seaweed, other composy -nothing, just straight manure. I had much better results last year using mostly loam. My leaves are only half the size of last year.
Anyway, thanks for your help and good luck to you both!

By the way, just for comarison sake, how big are your pumpkins now? How big are the leaves on your plant? When did your pumpkins get "set"?

Thanks again,
Chuck

7/28/2002 12:55:19 PM