Garden Mum Fertilizer Tips & Programs

Garden mums are available in a wide assortment of flower color and form, size, and bloom time. Since garden mums are a short day crop, they bloom naturally in the fall but may be forced to flower with shading. Flowering dates are also based on varietal choice that is grouped into early, midseason, late and season extenders. Growing garden mums is relatively easy in either 6" or 8" pans, 12" pots and larger containers. Some field production is still used for various niche markets - dig and swell. Growing garden mums provides the grower with fresh product to sell at the end of the summer and through until Thanksgiving in some parts of the country.
Media

Different soilless mixes can be used, including mixtures of peat, perlite, bark and sand. The media should provide enough porosity and be well drained. However during outdoor production, the media should be heavy enough to withstand wind and not topple over. It should be able to retain enough moisture outside between irrigations to provide good nutrition. The pH of the media should be between 5.5 and 6, and the EC should be 1.5 mS.

Fertilization

Garden Mums are heavy feeders. They require fertilizer immediately upon planting and rooted cuttings. Depending on water quality, various fertilizer programs may be followed.

Garden Mum fertilization, as with all crops, is dependent upon the quality of the irrigation water being used. High concentration of carbonates and bicarbonates will cause the pH of the media to rise during plant production. Water sources should be tested prior to deciding which fertilizer to apply. Options are available for various alkalinity levels. Acid injection (usually Sulfuric acid) is used when the alkalinity level is above 250 ppm CaCO3 for growers who want a consistent feed program. MPPI can provide water tests to determine your alkalinity level and general water nutrient levels. Based on your water analysis, we can determine which fertilizer schedule would work for you. When acid injection is used, Plant-Prod® Solutions 17-5-17 Complete could be used as a the general feed. Where Ca/Mg is low, use Plant-Prod 12-2-14 Optimum every third time.

If acid injection is not an alternative, rotation between acidic blends and a Cal Mag is suggested. The fertilizer analysis suggested would be determined by the water sample results but in general the following guidelines apply:

 

Water alkalinity between 75-100 ppm CaCO3 with low Cal/Mg levels:
Use Plant-Prod Solutions 17-5-17 at 200-250 ppm N as a constant feed. Every third time use Plant-Prod 12-2-14. Should the plants not size up enough due to climatic conditions, rotate with Plant-Prod 20-8-20 High Nitrate then return to Plant-Prod Solutions 17-5-17. If EC levels drop below 2.5 mS, increase the feed to 300 ppm N. Monitor EC and pH.

 

Water alkalinity between 150-250 ppm CaCO3:
Option 1 – If acid injection is not being used and the Ca/Mg levels are low, use Plant-Prod Solutions 19-8-13 Total Plus. Every third time, fertilize with Plant-Prod 12-2-14. If Ca/Mg levels are adequate, use Plant-Prod 20-8-20 at 200-250 ppm N on a constant basis. If EC levels drop below 2.5 mS, increase the feed to 300 ppm N. Monitor EC and pH.

Option 2 – If acid injection is being used and the Ca/Mg levels are low, use Plant-Prod Solutions 17-5-17 on a constant basis at 200-250 ppm N. Every third time, fertilizer with Plant-Prod 12-2-14. If Ca/Mg levels are adequate, then use Plant-Prod 20-8-20. If EC levels drop below 2.5 mS, increase the feed to 300 ppm N. Monitor EC and pH.

 

Water alkalinity greater than 250 ppm CaCO3:
Option 1 – if acid injection is not being used and the Ca/Mg levels are low, use Plant-Prod Solutions 18-9-18 pH Reducer at 200-250 ppm N constant feed. Every third time, fertilize with Plant-Prod 12-2-14. If Ca/Mg levels are adequate, use Plant-Prod Solutions 18-9-18 at 200-250 pH on a constant basis. If EC levels drop below 2.5 mS, increase the feed to 300 ppm N. Monitor EC and pH.

Option 2 – If acid injection is being used and the Ca/Mg levels are low, use Plant-Prod Solutions 19-8-13 at 200-250 ppm N constant feed. Every third time, fertilizer with Plant-Prod 12-2-14. If Ca/Mg levels are adequate, use Plant-Prod 20-8-20 at 200-250 ppm N constant feed. If EC levels drop below 2.5 mS, increase the feed to 300 ppm N. Monitor EC and pH.

Finishing

In order to maintain plant quality during shipping and sale, fertilizer rates may be reduced 3 weeks prior to shipping, or when the buds are pea sized. Plant-Prod Solutions 15-0-20 No-Stretch® should be used at 150-200 ppm N in order to strengthen the stems and to provide supplemental micronutrients to keep the finished plants greener.

Other Crop Production Programs