Category Archives: Nutritional Deficiency

phosphate deficiency in tomato plants

Identifying a phosphate deficiency in tomatoes

Today we noticed a phosphate deficiency in some of our tomato seedlings.  This particular deficiency manifests itself in a tomato plant on the underside of the leaf.  You will see a  purple color on the underside of the leaf while the top is the normal green.  Here is an example.

The underside of each tomato leaf in these seedlings were all showing the same symptoms

The underside of this tomato leaf has gone puple, indicating a phosphate deficiency
Phosphate deficiency manifesting in tomatoes

Corrective action for a phosphate deficiency

Now that you have identified the deficiency it is actually easy to correct.  My preferred correction is made with an application of 1/4 ounce per linear foot of 0-45-0.  It is more commonly known as triple super phosphate.

How long will it take to correct the phosphate deficiency?

Often your deficiency will begin to get better within a few days as a result of you applying a correction of the phosphorus. Be sure you remember to water the triple super phosphate in with a watering wand.  You want to make certain that the phosphate gets down to the roots where the plant can utilize it.

If after a week you don’t see any change give it another correction and consider other problems.

Is triple super phosphate organic?

Absolutely.  Rest easy, if you’re striving to stay organic you’re good to go.



Correcting nitrogen deficiency

Correcting nitrogen deficiency in beans

Recently we found ourselves correcting a nitrogen deficiency in our green beans.  They were beginning to turn yellow throughout the entire plant, meaning we have a nutritional deficiency.

To ensure we correctly identified the deficiency and made the right correction, we went to the MGC book.  On page 147 of the Mittleider Gardening Course shows us a general yellowing of the entire plant is a nitrogen deficiency.  It calls for a correction of 1/4 ounce per linear foot of nitrogen to be added.  The nitrogen should be worked into the soil and watered into the soil.

Urea is available locally, 46-0-0, so we will use it as our form of nitrogen.

Correcting nitrogen deficiency in green beans
correcting a nitrogen defeciency
urea was used to correct a nitrogen deficiency
urea was used to correct a nitrogen deficiency

What caused the deficiency?

It is normal to see deficiencies in your garden.  Some plants use more nitrogen than others, making them more susceptible to some form of nutrient deficiency .

In our case these beans were started in some recently mixed sand and sawdust in a grow box.  The natural decomposition  of that sawdust used up the available nitrogen.  One application of the urea 46-0-0 was enough to bring the beans green color back.

Recovery time

It may take a week or two for plants to recover if you have correctly identified the problem.  If after one week no improvement is seen then look for other possible causes.  As always, it would behoove the gardener to refer to the Mittleider Gardening Course book.