Unfortunately it isn't that simple. I'm only familiar with its use in hydroponics and detailed tables are available for it use in that situation - see the Hydroponics forum here if you want those. The amount used is done by weight, not volume, and it is measured in grams. (ie: 1 gram to 100 ml. of 40 C water) or if converted, approx. 0.03 oz. to 3.5 oz water at 104 degrees F.

Plus the mixture will be much weaker if used as a foliar spray or as a fungicide to avoid burning the plant leaves. And the solubility all depends on the temperature of the water you are using to dissolve it in - it is a very wide range of solubility.

You also have to factor in the effect it has on pH and when using soil rather than water your native soil pH has to be established first and then adjusted to compensate.

Then there is the issue of its use being banned in many states - especially if you live near a body of water of any kind - because of the run-off contamination. You don't give any location so I can't help with that aspect.

So all that said and acknowledging that there are much better giant vegetable fertilizers available (see the Giant Vegetables forum here) I'd recommend either finding one of the alternatives or at least posting this question on one of the many growing giant pumpkins forums out there in the hopes of finding someone who has actually used it for that purpose.

Contacting the maker of the particular brand for tips on dilution of their particular product would also be an excellent option assuming you'd need more details than just what is on the product label.

Hope this is of some help.

Dave

Here is what I have found, MonoPotassium Phosphate is the same ingredient used in some bloom and fruit fertilizers also known as MKP

MKP is a fully water-soluble mono-potassium phosphate fertilizer, a highly efficient source of phosphorus and potassium for plants. As a nitrogen-free fertilizer, MKP is the preferred source of phosphorus and potassium when nitrogen fertilization should be limited.

A common case is at early growing season, when phosphorus and potassium are needed at high rates for the establishment of root system.

Application of MKP at the productive stages of sugar-rich fruit crops helps to increase sugar content and to improve the quality of these.

MKP can be applied in combination with other fertilizers to meet crop nutritional needs throughout the growth cycle. Its high purity and water-solubility make MKP an ideal fertilizer for fertigation and for foliar application.

Additionally, MKP is suitable for preparation of fertilizer blends and production of liquid fertilizers.

When applied as foliar spray, MKP acts as a suppressor of powdery mildew.

Use approximately 1 (one) teaspoon of fertilizer per gallon of water for every 100 square feet of application area

For larger batches use 1 (one) pound of fertilizer per 100 gallons of water.

We have this product in bulk and repackage it into smaller sizes.