Produce Community

Protecting Watermelons from getting sun burnt?

Anyone ever heard of a product to protect watermelons from getting sun burnt?

Views: 718

Reply to This

Replies to This Discussion

There are a number of products that can protect watermelons and other melons from sunburn. The newest product, Screen Duo, has been used by melon growers in Australia for several years. A late high rate applications will provide sunburn protection. The same amount of material, applied at lower rates beginning at bloom, will improve flower set, melon sizing, and provide late season sunburn protection. Growers choice, but if started early, many of the yield losses experienced in the Southeast this season could have been reduced.

 

For more info, see cropstress.com or the Certis website.

There is a product call Crop Shield by Ultra Gro Plant Food out of Madera, CA.  You apply 1 gallon to the ac/ with low volume of water and you will get about 1 month pretection.  You can apply lower rates and apply more often as well if you only need heat stress protection for a shorter period of time.  We also include a NPK package in this as well.  Here are some pictures of treated and untreated blocks.  Here is in the central San Juaquin Valley we have summer temperatures between 95-105 degrees with no rainfall and depend upon surface and well water for irrigation.  Look at the attached file and you can see the effects that our product has on tomatoes.  Our web site is www.ultragro.net
Attachments:
We are currently observing significant losses in bell peppers due to sun scald in Michigan.  I assume this is too late to test some of those products now but will definitely try some next year.
Any sun scald that has already occurred cannot be reversed. However, if you have plants with small fruit, they can still be protected with Screen Duo.  In addition, growers in Australia also treat between pickings to protect interior fruit that become exposed after the first picking. One thing to know is that Screen Duo has two components with different ways of protecting plants against stress. This makes the material very versatile for early and late use patterns. For some information on heat stress ( sunscald is just a late symptom) take a look at www.cropstress.com. Please feel free to contact us with any questions.

Some of the benefits for using Crop Shield are the ease of application, it is not sticky, it is not a clay or seal the plant from breathing and continuing to grow.  It is not a polimer.  It protects both the plant and fruit from both heat and cold damage depending on the time of year.  If you have a heatlhy plant it is much more likely to protect itself from heat stress so nutritional balance is a must. 

Attachments:
When looking for a solar protectant, there are several now hitting the market, clay products as mentioned below like screen duo, surround, snow, cocoon etc. These are all dry products that have to be mixed in water and sprayed, often leaving a type of white-wash, they have been around a long time. Also there are like Abe mentioned several anti-transpirant products like Crop Shield, Sun Shield, Leaf Shield etc. they are very useful in transplanting and reducing stress on the plant due to high wind or heat, they haven't been shown to be as effective in protection against UV stress or sun scald. Then there are several newer technologies in the reflective category based on liquid calcium carbonate such as Purshade Ultra, Sombrero, Reflect, etc. They are designed to protect against the UV radiation (sunburn) and Infrared radiation (heat) to get improved protection against solar stress. Therefore there are many products to choose from, often it boils down to preference and grower experience. There are many university trials out. Call your local distributor and ask them for a recommendation. Hope that helps.
Riley's comments are excellent. There is one that needs some correction. Screen Duo is an entirely new concept in solar protectants. It was designed with two active components, a kaolin reflectant and a naturally-occurring terpenoid compound that activates the stress protective mechanisms of the plant. This is unique to Screen Duo; a patent has been applied for these combinations. The advantages are lower rates (less film) no rainfast issues, two modes of action for activity under extreme conditions, less material to handle. Please not that there is an inherent technical problem with calcium carbonates. They absorb radiation in the high energy UV, which is converted to heat, reducing the desired effects. Also, in head to head trials, they are less effective than a product such as Screen Duo. These technologies are actually quite old, Purshade based upon Eclipse has been around for 25 years. It was only recently repositioned for solar protection. Anyway, go with the science and compare any data available to decide.
Gentlemen, as you may already know Mr. Chuck Kupatt is an owner/manager of the company that manufacturers Screen Duo. I am the Technical Director for Purfresh who manufactures Purshade, and Abe Isaak works for Ultra Gro. I tried to stay neutral and post basic information, but the last post was pretty misleading, especially the UV info and that Eclipse is Purshade, that is incorrect information, nor has the technology been used for 25 years. New technology is being developed constantly. Let's keep the blogs civil, truthful and informative. Anyone wishing to find more information about Purshade is invited to visit our website at www.purshade.com

I use Kaolin clay and it works well

Unfortunatley, there are products that claim to solve nearly every problem under the sun, no pun intended!

The basic problem occurs due to a lack of vine cover with regards to sunburn or scalding on melons cucumbers and yes bell pepper as well. Growers and consumers should be weary of any product that makes claims of preventing or minimizing sun scald by any means other than improving the growth of canopy, which has multiple roles in production. Other than receiving sunlight canopy also serves the purpose of shading the crop! The only products that we are aware of should be used early on in the growing season and work in the soil to improve plant vigor and growth. As is the case with most ailments Prevention is the best medicine. If you are experieincing symptoms such as whitewashing, sunburn, or scalding it is merely an indicator that other significant problems are occurring in the crop!

Maintaining a good canopy is important and can reduce sunscald, but it is incorrect to say that there are no products that can reduce the damage. There is a wealth of data in numerous crops demonstrating the reduction in solar injury using materials that reflect light, as well as some biochemical materials that reduce the impact of the stressors on the crop. Of course, heat light water, and cold stress can all negatively impact canopy, so protecting the foliage from these stressors is beneficial.Plus, maintaining photosynthesis at higher rates due to the stress amelioration results in higher yields as well as improved quality. This is the next step in agricultural productivity. Proof that these materials work comes from what happens after harvest. In many places, the melons are left out under the sun. There are significant reductions in melon losses even under these types of handling. I suggest doing side-by-sides to see the difference and measure the benefits. Then calculate the return on investment. We typically see 3-8x ROI. For more info, www.cropstress.com.

Please do not mistake my comments. After reviewing my post it is clear there was no comment regarding whether or not there are products that can reduce the damage. Contraire, we have experience with a particular product that has demonstrated at the University level, replicated studies, showing significant improvements regarding vine cover and reduced "whitewashing" in watermelon crops. My wish was to shed some light on the subject from another perspective and with other facts to consider that had not been discussed. Again, one of the most critical things in melon production is to produce a very good vine that protects and shades the fruit which is the best and natural defense of these symptoms...so if you have products that help, great!

Reply to Discussion

RSS

© 2013   Created by Allison Bray.

Badges  |  Report an Issue  |  Terms of Service