Weather conditions throughout the United States and Canada this summer have really run the gamut, from record-setting heat and drought in Texas to cool temperatures and high rainfall in Illinois — and that's thrown some growing operations for a loop.
Syngenta Flowers has been getting a lot of calls from growers about the wacky weather and its effect on their chrysanthemum crops, so they had breeder Mark Smith put together some information on how to manage mum production in light of that.
"Here's an explanation of what is happening with your plants and some simple crop management techniques for the rest of the mum growing season. If you are lucky enough to have production in an area not affected by these out-of-the ordinary weather conditions, we offer some continued crop management tips.
"Unusually cold nights, combined with extended periods of cloudy and rainy weather, do not create a great environment for getting garden mums off to the best start. These weather conditions have caused increased levels of budding or, in severe cases, premature flowering. Both budding and premature flowering results in smaller than desired finished plants. Your best line of defense is a strong liquid feed program to keep early budding at a minimum and allow the plant to build size before flowering. It is important to refeed after a rain to be sure there is still fertilizer in the pot until the next irrigation cycle. If you are seeing large size buds that look like they could develop into flowers, you will likely need to kick start your plants back into growth with a 500- to 600-ppm nitrogen liquid feed application. A second application may be necessary. Be sure the plant's roots are healthy and actively growing before applying these booster feeds.
"If you have been fortunate enough to miss the cold nights and have seen the sun in June and early July, you probably are working on some feed level reductions to tone your plants and keep them at your desired size. The first plant stage for reduction is after secondary branching has started or roughly when the plant covers the pot. Cutting the fertilizer rate by one-third (e.g., 300-ppm N to 200-ppm N, or 350-ppm N to 250-ppm N) reduces fertilizer costs while allowing continued growth to make finished plant size. The next fertilizer reduction occurs when the plants are 65 to 75 percent of their desired finished size. At this point, switch to a maintenance feed level of 50- to 100-ppm nitrogen two or three times a week, with clear water in between. This prevents overgrowth and flowering delay while adding plant strength and reducing your input costs.
"Fusarium and/or Pythium can be common root diseases in mum production. Heritage and Medallion are very effective against Fusarium and can be alternated about every four weeks after planting. Truban is effective against Pythium and commonly applied about six weeks after planting. Be sure to follow the Truban with a water irrigation of half the drench volume."
For more information on mum production and crop management, visit Syngenta Flowers' website .