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​In years past, the European corn borer was the most important pest of sweet corn, as well as being a pest of peppers and other vegetables. Since the advent of Bt field corn, the overall population of corn borers has been dramatically suppressed, so far that we often forget about it being a pest of sweet corn. However, occasionally the corn borers like to remind us that they are still around and can still be damaging to our crops. These outbreaks usually occur in the northern part of the state, often in areas where the landscape is not dominated quite as much with field corn and soybeans. Corn borers have a broad host range, so diverse habitats provide them with a choice of suitable foods. Management of corn borers in sweet corn is relatively easy. As your sweet corn approaches tasseling, look for corn borer feeding and confirm that borers[Read More…]


​We are again seeing a lull in pheromone trap catches of corn earworms. However, I caution sweet corn growers to remain vigilant in checking their traps. Populations can increase rapidly, especially if carried north on storm fronts from the Gulf Coast. It is also important to watch the development of the field corn around your sweet corn fields. If the field corn is not yet silking, use a threshold of 1 earworm moth per night to determine if you need to spray when your sweet corn is silking. If the neighboring field corn starts to silk, it will draw a lot of earworm moths away from your sweet corn and the treatment threshold goes up to 10 moths per night. Particularly during this lull in moth flights, this is an opportunity to save money and time by avoiding spraying silking sweet corn.


​Populations of striped cucumber beetles continue to remain high. Muskmelon and cucumber growers should continue to monitor and spray as needed to avoid transmission of the pathogen that causes bacterial wilt of cucurbits. Wilt symptoms are showing up on melons throughout the state at this time, with greater prevalence in the southern counties and less further north. Growers are encouraged to spray as late in the day as possible, preferably after the flowers have closed and the bees have left the field, so that effects on pollinators are minimized.


Boiler Hops Logo

​Burrs and Cones. Both of the trellises in the Boiler Hopyard have begun flowering and coning. The primary shoots were pruned at the top of the net on the dwarf trellis in order to promote lateral growth. The pruning took place on May 19 and again on May 28. The bines on the dwarf trellis have been flourishing with flowers and now cones. Out of the six cultivars in the hopyard, Galena was the first to reach the top of the dwarf trellis and begin flowering. The tall trellis began flowering in early June along with the dwarf trellis, but after adding the last dose of nitrogen the plants in the tall trellis began putting on more vegetative growth, including lateral branches. This appeared to delay flowering and allowed for more lateral growth development. The plants in the tall trellis are now in full bloom and appear to be several[Read More…]


​Yellowstriped armyworms continue to cause problems for tomato growers, especially in high tunnels. The populations are often spotty within a field or high tunnel, but can easily reach damaging levels. Most of the insecticides listed in the Midwest Vegetable Production Guide for control of caterpillars on fruiting vegetables (pages 135-6) will control yellowstriped armyworms. If spraying within a high tunnel, be sure that the label allows use in a greenhouse or high tunnel. Consult Table 16 on page 40 for available options.


Note that the Wabash River is visible through the break in the trees.

​With the record-setting rainfall we’ve seen over the past month, flooding of fields is very widespread (Figure 1). Fields that have experienced flooding present growers with difficult management choices. Flooding is defined (per FDA) as the “flowing or overflowing of a field with water outside a grower’s control.” Flooding is associated with streams, creeks, or ponds that overflow their banks and cannot be controlled. The FDA considers food contacted by flood water to be “adulterated” and not fit for human consumption. Due to microbial and other concerns, produce cannot be harvested and sold into the public food supply once it contacts flood water. Frequently, only a portion of a field is affected by flooding. If only part of a field is affected and flood water contacts the edible portion of the crop, growers should manage the contaminated crop so that it does not affect uncontaminated crops. To protect uncontaminated crops,[Read More…]


​Growers may be wondering whether to replant pumpkin fields where the stand is uneven due to excess moisture. Potential yield of the replants is one thing it would be good to know. We have data on yield of pumpkins direct-seeded or transplanted in mid-July in northern Indiana. The trials were no-till planted into a harvested wheat field. Pumpkins were harvested in mid to late October. Yield of direct-seeded pumpkins ranged from 0 to 0.6 tons per acre for 8 varieties in 2004, and from 2.6 to 6.4 tons per acre for 5 varieties in 2005. Yield of transplanted pumpkins ranged from 2 to 8 tons per acre for 8 varieties in 2004 and from 4.4 to 9 tons per acre for 5 varieties in 2005. For comparison, typical yields at this site for an early- to mid-June planting date with conventional tillage range from 10 to 25 tons per acre.[Read More…]


Sweet corn ready for sampling.

​Pinney Purdue Vegetable Field Day and Sweet Corn Sampler. Thursday, August 13, 2015. 4:00 p.m. – 8:00 p.m. CDT. Pinney Purdue Ag Center, 11402 S. County Line Rd., Wanatah, IN. Plot tours include soil health management and disease suppressive soils, tomatoes and peppers in high tunnels, and sweet corn varieties. To register, contact Lori Jolly-Brown, ljollybr@purdue.edu, or 765-494-1296.


I’ve seen some substantial populations of potato leafhoppers recently. Leafhoppers can be a significant pest of a number of vegetable crops, with potato and snap beans being particularly affected. Look for adults flitting off the plants when they are disturbed and for nymphs feeding on the underside of the leaves. It is important not to wait until you see symptoms (hopper burn) before you take action. Scouting is the best way to avoid leafhopper injury.


(Photo by Dan Egel)

​Bacterial spot of tomato causes lesions on foliage and fruit of tomato. On leaves, the lesions begin as small water soaked areas and turn into brown lesions with a yellow halo. Lesions on stems often lack a yellow halo. Fruit lesions, which are responsible for direct loss of marketable yield, are often scabby in appearance (Figure 1).  Bacterial spot of tomato is favored by warm, wet weather. The causal bacterium survives on crop debris and may be seed borne. Volunteer tomatoes and peppers may also carry the disease. Transplant greenhouses should be cleaned and sanitized after each generation of transplants is produced. Management of bacterial spot of tomato has been covered in more detail here https://ag.purdue.edu/arp/swpap/VeggieDiseasesBlog/Lists/Posts/Post.aspx?ID=31. The Midwest Vegetable Production Guide for Commercial Growers 2015, also has recommendations.  In this article, however, I would like to discuss a new product that has recently been labeled for this disease. Quintec® has been labeled for[Read More…]


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