A & L Southern Agricultural Laboratories, Inc.

1301 W. Co pans Road. Building D, Suite 8' Pompano Beach, FL 33064

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By: Lynn P Griffith 01/06/10

Five different plant types were grown in a commercially produced potting media at three different fertilizer incorporation rates, with and without Turf Pro added to the media. Spathiphyllum, blueberries, azaleas, mandevillas and begonias were consistently and significantly larger in size and higher in plant quality than plants grown without Turf Pro. Plants with somewhat lower fertilizer requirements such as blueberries and azaleas did as well or better at the lower fertilizer rates. Plants with higher fertilizer requirements such as spathiphyllum did better at the high fertilizer rates.

Potting media containing 20% Canadian peat, 20% Florida peat, 30% Pine bark and 30% Cypress sawdust by volume was obtained from a commercial producer. The mix had 20 pounds per cubic yard of dolomite and 20 pounds of Turf Pro incorporated, along with four pounds of Meg iron micronutrients. Two cubic yards of potting media were obtained without granular Turf Pro incorporated, and two cubic yards were obtained with Turf Pro.

Seventy two cell liners were obtained from a commercial source. The varieties were spathiphyllum "Debbie", Ambassador Rose begonia, yellow mandevilla, Southern Belle blueberry, and azaleas. The variety of azalea was not identified on the liner flats, though it appeared to be a common variety of landscape azalea. Four fertility regimes were employed, no fertilizer, 15 pounds of 19-6-12 eight to nine month Osmocote incorporated, 12 pounds of 19- 6-12 eight to nine month Osmocote, and 9 pounds of 18-6-12 eight to nine month Osmocote. Turf Pro was also applied in liquid form to blueberries, using the same four different fertilizer incorporation rates. The liners were selected for uniformity and planted in new, plastic ten inch pots, and placed in a randomized block design. Treatments were identified by different color dots of spray paint on the side of the container. A dot of red spray paint was used for plants without Turf Pro, a green dot for plants with Turf Pro. The high fertilizer rate was indicated by a gold dot of spray paint. The medium fertilizer rate was identified by a silver dot and the low fertilizer rate by a white dot. Plants were grown for three months on a raised bench, undercover, so that rainfall was not a factor. Each planting was replicated five times.

Plants were irrigated with well water on a pot by pot basis, making sure that a uniform amount of irrigation water was applied to each container each time in order to avoid sprinkler system variation. The pots were irrigated using a garden hose with a water breaker, with each pot being irrigated for a uniform number of seconds using a counting system. As the plants grew, the quantity of irrigation per application increased by about 50%. Irrigation was generally about twice a week, though it ranged from one time to three times per week depending on weather conditions. The same regime was applied to begonias, though they were potted in full one gallon pots and were grown in full sun on the ground in order to simulate typical nursery practice. No fungicide or insecticide sprays were applied over the course of the study. Temperature ranged from a high near 90 to a low of 42 degrees during the three months of the study, which was conducted during the fall of the year.

For the application of liquid Turf Pro, three gallon blueberry plants were irrigated each time with liquid Turf Pro, using the hose-on application bottle in which the liquid product is sold. Each plant was watered in a uniform fashion, the same as the rest of the plants in the study, using a measured amount of irrigation water with liquid Turf Pro. The liquid product was applied at each watering, and plants receiving the liquid product were watered at the same time as the plants in the rest of the study. Half of the blueberry plants had no incorporated granular Turf Pro and only received liquid product. The other half had granular Turf Pro incorporated, with liquid Turf Pro added as well at irrigation.

Crop size and quality ratings were taken at 30 days and 90 days after planting. Crop size was measured by multiplying the height times the spread times the root mass, the larger the number indicating the larger the plant. Crop quality ratings were made using a 0 - 10 scoring system, with 0 being a dead plant and 10 being the best possible rating. The data after 30 days
showed no real differentiation, as I think it was just too early to see much difference. The 90 day data are presented in the tables below.

Table 1 shows that without any fertilizer whatsoever, plant growth and quality was not particularly good, though there was a response to the Turf Pro with all five plant varieties, though the spathiphyllum difference is probably not significant. The Turf Pro generated a growth response in the plants in the absence of added fertilizer.

At the high rate of incorporated Osmocote, growth rates were dramatically different with Turf Pro. The difference was especially dramatic with the azaleas. Two of the test plants at the high fertilizer rates without Turf Pro died, whereas all of those with Turf Pro lived. Plant quality ratings were significantly better with the Turf Pro as well for all plant varieties tested.

At the medium fertilizer rates, spathiphyllum, azaleas and begonias grew significantly better with Turf Pro. Growth was about even for blueberries, and worse for mandevilla, primarily because one of the test plants had died. At the low fertilizer rate, spathiphyllum, blueberries, azaleas and mandevilla grew substantially better in the Turf Pro plots. Begonia growth was about the same.

In Table 2 for plant quality, the plant quality ratings included plant color, plant form, and leaf size. Plant quality ratings generally mirrored the plant size ratings. Quality ratings were consistently and significantly better in virtually all of the Turf Pro plots, with the exception of the mandevilla at the medium fertilizer rate.

Using only liquid Turf Pro, the blueberries did not grow as well at the high fertilizer rate as they did at the medium and low rates. With both granular and liquid Turf Pro, growth was significantly better, though the blueberry plants did best at the lowest fertilizer rate with both types of Turf Pro in use. Plant quality ratings were better with both liquid and granular Turf Pro as compared to using the liquid only. Plant quality ratings with liquid Turf Pro only were comparable to the granular product. Plant quality ratings were also similar between the liquid plus granular Turf Pro to the granular Turf Pro only.

The data suggest several things. One is that the Turf Pro inoculant seems to impart some sort of synergistic effect between the plant, the soil and the fertilizer. Whether fertilizer was used or not and at all three rates, plants generally did better with the Turf Pro product. Blueberries, having a lower fertilizer requirement than the ornamental varieties tended not to do as well at the higher fertility rates in some cases, though at higher fertility rates with Turf Pro they did better. The growth rates and quality levels of blueberries were greatly enhanced at the lower fertilizer rates. Field grown blueberries generally receive only about 1/10th the amount of nitrogen per acre per year that spathiphyllum do, so the better performance at lower fertility inputs is not surprising. Azaleas also have lower fertility requirements than many tropical foliage plants. The data with azaleas suggest that azaleas may be grown successfully at lower fertility rates when Turf Pro is used. The loss of two of the test plants without Turf Pro could be related to either soluble salts or disease. Some of the data for mandevilla also suggests that lower fertility inputs may be utilized if the Turf Pro product is included in the production program.

With the heavier feeding varieties such as spathiphyllum and begonia, plants still generally did significantly better at the higher fertilizer rates. At the high fertilizer rate, spath and begonias grew consistently better and had higher plant quality ratings with Turf Pro granular than without. In this study, the incorporation of granular Turf Pro into the potting media clearly resulted in larger plants of better quality than the untreated controls.

2011A 9/17/10

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