isp fruit set

ISP Technologies Greenhouse Tomato Program

Greenhouse tomatoes, fresh market, heirloom, paste, cherry, grape, sweet bell peppers, hot peppers; the choices are almost endless when it comes to growing tomatoes, peppers or even eggplant. In all instances though, an essential goal is to produce high yield with outstanding taste and shelf life. Accomplish those goals and the rewards can be great. Both wholesale buyers and retail consumers are searching for many of the same characteristics, with the primary one being taste.

Another similarity is the way that these plants tend to grow and set fruiting forms. Once we understand the concept of managing our crop for vegetative development, fruit set, fruit size and quality, we can then use this knowledge to improve many of our produce crops.

We all know that yield is the result of management decisions, but we also need to be aware that taste can vary tremendously … even with the same variety of tomato or pepper. Grow the “perfect” tomato or pepper and the world will “beat a path to your door.”

Heirloom varieties can open a new path for farmers to enter niche markets. Heirloom seeds start with more nutrition, is the quest for eating tomatoes or nutrient dense tomatoes? There are many varieties and flavors

The flavors are endless

The flavors are endless



Cass City, Michigan

 Soilfriends michigan local produce tomato soil program

Soilfriends Local Produce


The ISP Tomato & Pepper Program provides you, the grower, with the tools to accomplish higher yields and significantly improved quality.

1. Ensure that your soil has high levels of fertility.

2. Transplant solution: (example: 100 gal. of solution, add 6 – 10 lbs. 10-45-10, 16 oz. Seed Boost, and 1 – 2 quarts PhytoGro.) Irrigate enough to settle the soil around roots.

3. Allow transplants to dry somewhat to encourage root growth, then water as necessary (2 – 3 times per week).

4. After transplants are exhibiting new growth; add 2 – 5 lbs. 10-45-10, 4 oz. HV-1 per irrigation. Every 3rd irrigation, replace 10-45-10 with 32 oz. MetaCal.

5. Continually observe and evaluate plant growth. Pay attention to lower leaves and the growing point, which should always appear “fresh”. (See photo bottom right)

6. Once first flower buds appear, foliar 2 – 3 lbs. 10-20-20, 6 oz. epsom salt, and 2 – 4 oz. Seed Boost for each 12” of plant height. Repeat every 7 – 10 days.

7. Once pea size fruits appear, add 28-16-7 to both drip and foliar applications. The ratio of 28-16-7 to 10-20-20 will be based upon main stem node spacing. Total plant food application will be from 2 – 4 lbs. per foot of plant growth. Maintain MetaCal (1 qt. per week).

8. Once initial fruits are 1”, begin using 4-18-38 and 28-16-7 at 2 – 3 lbs. each per irrigation day. Increase MetaCal to 2 qt. per week. If base saturation of calcium is less than 65%, use 3 qt. through the drip, and foliar 1 qt. per week.

9. By the time early set fruits are ripening, nutrient will be applied through the drip with each irrigation. 4-18-38 will make up about half of total nutrient applied, but 28-16-7, 10-20-20, either Seed Boost or HV-1, and certainly MetaCal are all still important. We recommend at least two foliars per week to supplement drip applied nutrient.

Amount of total nutrient will vary based upon plant size and fruit set, with amounts being increased as the number of fruits increase. The most common mistake is to start strong, setting high numbers of fruit, then failing to increase nutrient applications as total fruit load increases. Continue to watch the lower leaves, the “freshness” of the growing point, bloom abortion, and the size of the maturing fruit. All of these are indicators of adequate or inadequate nutrition. Remember that as fruit set increases, so does the need for water!