Progress 10/01/17 to 09/30/18
Outputs
Target Audience:Greenhouse ornamental growers. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?
Nothing Reported
How have the results been disseminated to communities of interest?Oral presentation at Cultivate 17 in Columbus OH. What do you plan to do during the next reporting period to accomplish the goals?Future experiments will focus on rates and frequency of application of organic fertilizers in addition to increase the types and brands of organic fertilizers which will be tested.
Impacts
What was accomplished under these goals?
Experiment 1 Objective:To determine the effect of organic fertilizers on growth and quality of poinsettia plants. Materials and Methods Rooted poinsettia cuttings cultivar Peter Star were planted in 6 inch diam. (1720 ml volume) standard plastic containers using a Fafard 3B substrate without fertilizer charge and located on a bench of a greenhouse at The OSU, Columbus. Plants were not pinched. Treatments: 1) Water soluble fertilizer (WSF) Peters 20-10-20 at 100 ppm N; 2) Controlled release fertilizer (CRF) Osmocote 15-9-12 (5-6 month) at 3.4 g/L; 3) Organic fertilizer MiracleGro Organic Choice 7-1-2 (MGOC) at 7.3 g/L; 4) Organic fertilizer Sustane 8-4-4 (ST) at 6.3 g/L; 5) Organic fertilizers Verdanta 7-5-10 plus N-Vita 9-4-3 at 1.8 g/L plus MNM 2-0-1 micronutrient fertilizer at 0.9 g/L (As suggested by Bioworks and called here Vita- Fertilizer or VF); 6) Fish fertilizer FishRich 2-2-2 (FR) emulsion at a rate of 18 ml/L. The CRF and the solid organic fertilizers were applied as pre-plant incorporated. These plants were irrigated with tap water as needed depending on environmental conditions and plant size. The WSF and FR were applied as fertigation "as needed" depending on environmental conditions and plant size. Five weeks after planting, plants in the solid organic fertilizer treatments were divided into two groups. One started receiving the FR fertilizer at the same rate as the fish fertilizer treatment while the other half received only tap water. This fertigation process continued until plants were harvested. After harvesting the above ground part of the plant, shoots were placed individually in paper bags and located in a drying oven at 55 °C for 3 d. After that, dry weight (DW) of each plant was measured. In addition to DW, plant height, SPAD readings of the upper and lower leaves were taken using a SPAD-502 meter (Konica Minolta Sensing). Three upper green leaves (right below the bracts) and three old leaves in the lower part of the canopy, were SPAD-measured. The area of the colored bracts of the inflorescence of each plant was measured using a LI 3100 Leaf Area meter (LiCor, Lincoln, NB). The experiment consisted of 6 fertilizer treatments. Six plants per treatment were placed on a greenhouse bench as a complete randomized design. ANOVA test was conducted using the software StatisticX 9. Results and Discussion WSF-treated plants were the tallest with an average height of approximately 40 cm. It can be speculated that high rates and constant phosphorous fertilization from the WSF produced plant stretching. There was no difference in height between plants treated with CRF or the FR fertilizer. For poinsettia plants initially fertilized with ST or MGOC, the fertigation with FR fertilizer during the second half of the crop resulted in taller plants. That effect was not seen for plants initially fertilized with VF. Except for WSF-treated plants, height differences among treatments were small from a practical point of view. The largest plants were obtained when they were fertigated with WSF. Addition of nutrients at each fertigation resulted in substantially larger plants. The second largest plants were those treated with CRF; they were 12.5% smaller than WSF-treated plants. In the case of ST- and VF-treated plants, the addition of FR fertilizer during the second half of the crop resulted in heavier plants. No effect of FR was noted on MGOF-treated plants. CRF-treated plants had a larger bract area than WSF-treated plants. Application of FR resulted in increased bract area in plants of all treatments that received FR. There was no significant difference in bract area among FR treated ST, MGOC and VF plants. It was obvious that the VF-treated plants did not have enough nutrients to produce an attractive bract area of the main inflorescence. Differences in SPAD readings among plants treated with FR fertilizer were small. Addition of FR fertilizer in the second half of the crop resulted in higher SPAD reading (greener leaves). No differences in SPAD readings of upper leaves were found between WSF- and CRF-treated plats. Except for WSF- and FR-constantly-treated plants, there were differences in SPAD readings of upper vs. lower leaves. In the case of VFs-only-treated plants, there were no lower leaves present on the plants probably due to leaf abscission caused by low levels of nutrients. Conclusion: Based on these results we hypothesize that the combination of a pre-plant solid organic fertilizer followed by fertigation of a soluble/emulsion organic fertilizer will produce a poinsettia crop with salable characteristics. This hypothesis will be tested in a future experiment. Experiment 2 Objective: To evaluate the feasibility of growing bedding plants using only a liquid organic fertilizer. Materials and Methods Plugs of petunia (Petunia x spp) were planted in 4.5 inch diameter plastic containers using a Fafard 3B soilless mix without fertilizer charge and located on a bench in a glass greenhouse at The OSU, Columbus. Plants were irrigated with tap water as needed based on plant size and environmental conditions. Approximately twice a week, plants were fertigated with a FishRich (Bell Aquaculture, Redkey, IN) (FR) fertilizer which is a fish based fertilizer. Rates of application were 31 ml/L (1X, or company recommended rate), 46.5 ml/L (1.5X), 5.5 ml/L (0.5X), and water only as control. As a point of reference, one treatment consisted of plants fertilized with Osmocote 15-9-12 (5-6 month longevity, CRF) at a rate of 3.4 g/L substrate. Six weeks after planting, number of flowers and flower buds were counted and above ground plant parts were harvested, placed individually in paper bags, and located in a drying oven at 55°C for 3 days. Subsequently, dry weights (DW) were measured. Results and Discussion Petunia plants fertigated with FR at a rate half of the recommended rate (0.5X) were not different in quality and size from those receiving the CRF. Inherently, increasing rates of application of FR results in smaller plants. Control plants did not grow confirming that the substrate had no nutrients for plant growth. No significant differences in the number of flowers and flower buds was found between the 0.5X FR and the CRF plants. The 0.5X FR treatment had plants with significantly larger number of flowers and flower buds (8.75 per plant) than plants in the 1X (6.5 flowers) and 1,5X (1.85 flowers) treatments. Future experiments will focus on rates and frequency of application of FR.
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Progress 10/01/16 to 09/30/17
Outputs
Target Audience:The target audience is primarilygreenhouse growers of ornamental crops. Results could be beneficial aslo for organic growers of some other crops like vegetable crops. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?No opportunities for training and professional development were provided. How have the results been disseminated to communities of interest?At this point, the results have been disseminated only among growers that I have contacted personally during my Extension contacts. What do you plan to do during the next reporting period to accomplish the goals?I intent to continue testing different approaches of application of organic fertilazers using different crops.
Impacts
What was accomplished under these goals?
EXPERIMENT 1 Objective To evaluate the feasibility of using a liquid organic fertilizer as a supplement to the pre-plant application of already tested solid organic fertilizers. Materials and Methods Plugs of 'French' thyme (Thymus vulgaris), 'Goldstrum' rudbeckia (Rudbeckia fulgida), Italian parsley (Petroselinum crispum), and catnip (Nepeta spp.) were planted in 4.5 inch containers using a Fafard 3B mix without fertilizer charge and located in a greenhouse at Ohio State University.Before planting, 1 of 3 fertilizers were incorporated in the substrate of each container.Fertilizers were: Osmocote 15-9-12 (5-6 month longevity, CRF), Sustane 8-4-4 (SUS), and MiracleGro Organic Choice 7-1-2 at the following rates of application: Osmocote, 6.5 lb?cy-1, Sustane, 12.2 lb?cy-1, and Miracle Gro, 14.4 lb?cy-1. All plants received the same amount of N and were irrigated with tap water as needed. Six weeks after planting, 50% of plants started to be fertilized twice a week with the liquid organic fertilizer FishRich (Bell Aquaculture, Redkey, IN) at the recommended rate of 4 oz/gal.Other than these 2 weekly fertigations, plants continued to be watered as needed.The other 1/2 of the plants were irrigated with only tap water.Above-ground plant parts were harvested 12 weeks after planting (WAP) for parsley, 15 WAP for Nepeta, 18 WAP for thyme and rudbeckia and placed in paper bags and located in a drying oven at 55°C for 3 days.After that, DW were measured. The experiment consisted of 7 treatments: 3 fertilizers applied pre-plant, 1 fertilizer applied after 6 weeks to half of all plants, plus a control (no fertilizer). Six plants per treatment were placed on a greenhouse as a complete randomized design. Results are expressed as means plus/minus standard errors. Results and Discussion Six weeks after planting, all thyme plants were similarly green, while CRF plants were slightly larger.All plants except controls were of saleable quality.At 18 WAP, Thyme plants grown with only CRF were slightly larger than those receiving only organic fertilizers.When no FF was used, no differences in DW were found among plants grown with either the 2 organic fertilizers. Control plants did not grow and had yellow leaves. Plants receiving FF were, for each fertilizer type, larger than those receiving only the pre-plant organic fertilizer. Again, the plants receiving CRF were the largest and no differences in DW were found between the plants receiving the 2 pre-plant organic fertilizers.The Control plants that received FF recovered rapidly, showing green leaves and larger DWs. Rudbeckia plants grown with only CRF were slightly larger than those grown with either of the 2 organic fertilizers.Plants grown with MG fertilizer were the smallest and significantly smaller than those grown with SUS.Plants with no fertilizer did not grow.Plants receiving FF were larger than those not receiving this fertilizer. However, the differences in DW between plants receiving the additional FF were not significant.Control plants responded well to the FF reaching a size similar to that of plants fertilized only with MG. Except for parsley plants grown without fertilizer, all other had similar DW regardless of the fertilizer applied. Applying FF resulted in larger parsley plants when a pre-plant of CRF or SUS was applied but not when pre-plant fertilized with MG. The difference in coloration between plants treated with FF and those without were clearly visible. In some cases, like CRF treated plants with no FF applied, some of the foliage was pale green. Catnip plants grown with only CRF were larger than plants grown with only SUS or MG.These 2 organic fertilizers produced plants of similar DW. FF-treated plants were larger than plants without FF. The response of the Control plants to FF was dramatic.In a short period, they grew to saleable plant sizes.Plants not receiving FF were noticeably paler with many of them showing yellow old leaves and loss of old leaves. EXPERIMENT 2 Objective To measure nutrients (Nitrogen, phosphorous, potassium, and iron) in leachates from basil plants grown with two organic fertilizers and one controlled release fertilizer. Materials and Methods Plugs of 'Sweet Italian' basil (Ocimum basilicum) were planted in 4.5 inch diameter plastic containers using a Fafard 3B soilless mix without any fertilizer charge and located in a greenhouse at Ohio State University.Before planting, one of 3 fertilizers were incorporated in the substrate of each container.These fertilizers were: Osmocote 15-9-12 (5-6 month longevity, CRF), Sustane 8-4-4 (SUS), and MiracleGro Organic Choice 7-1-2 at the following rates of application: Osmocote, 6.5 lb?cy-1, SUS, 12.2 lb?cy-1, and Miracle Gro, 14.4 lb?cy-1.All plants received the same amount of nitrogen (N) and were irrigated with tap water as needed. The experiment was conducted during fall and the greenhouse temperature settings were 70 day - 75 F night. Each container was placed on a 5 by 5 inch mesh on top of a 4.8 inches diameter bowl. Plants were monitored daily. Plants received 400 ml of tap water each time they were irrigated.This volume resulted in leaching rates between 20 and 30 %. Leachates were collected each time plants were irrigated and their volume measured. Irrigation events occurred on 12/30, October 7, 12, 19, 23, 27, November 2, 6, and 9. Up to 50 mL of leachates were frozen and stored at -10 °C for future measurements of N, P, K, and Fe.Nutrient concentrations were measured at the OARDCSTAR Laboratory in Wooster, Ohio. The experiment consisted of 3 treatments: 3 fertilizers applied pre-plant.Six plants per treatment were placed on a greenhouse as a complete randomized design. Results and Discussion The 3 fertilizers leached a moderate amount of N the first week of leachate collection.The amount of N increased to a maximum at either the first or the second collection (depending on the fertilizer), it decreased thereafter, remaining constant from the seventh collection to the end. Of the 3 fertilizers, SUS is the one which leached more N while CRF and MG released similar amounts of N.Most N was leached soon after planting. CRF leached around 0.2 mg of P the first 3 dates of leachate collection and decreased thereafter reaching a minimum the last date. The 2 organic fertilizers had a pick of P lost on the third date and slowly decreased over time.However, towards the end, the two organic fertilizers released more P than the CRF. The differences in cumulative P leached between fertilizes were smaller than for cumulative.The pattern of the curves describing cumulative P for the three fertilizers was almost linear over time indicating that the release of this nutrient occurred over the whole cycle of leachate collection. The pattern of release of K over time for the 3 fertilizers are similar to that of N: initially intermediate, reaching a maximum the second or third date of data collection and decreasing thereafter. Potassium in leachates from fertilized with SUS was very high the 4 first dates of leachate collection.After the sixth date of collection, K from SUS was similar to MG and constant for the last 3 dates of collection.Containers fertilized with SUS lost the largest amount of K. CRF plants lost the least K with plants fertilized with MG losing intermediate amounts. The highest amount of Fe leached was observed for plants treated with CRF on the third week of leachate collection.Potassium leached from CRF treated containers was always higher than from containers treated with SUS or MG, except for the last date of leachate collection.After the fourth date of data collection, there were no differences in K leached from the SUS or MG treated containers.Containers treated with CRF lost the highest amount of Fe, followed by those treated with SUS and followed by those treated with MG.
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