Category: Organic Chocolate Farm

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Protecting our Cacao from the Chinese Rose Beetle

Quicklinks to Organic Field Tests

Are you trying to fend off the Chinese Rose Beetles that are eating your precious Cacao trees or even worse-destroying a new orchard that you are working hard to establish? 

If yes, we have something in common. Ocean Grace Farms, LLC. is in its transition to 100% organic. As a Hawaiian Cacao Farm one of our biggest obstacles, in this mission, is the Chinese Rose Beetle. This pest is more of a problem when you are establishing a new orchard and have younger trees; which we are and do. If you are learning about the Rose Beetle, here is a great resource that we found via CTAHR: Chinese Rose Beetle: Problem, Description and Information.

Cacao Tree in Protective Cage For one stage of protection making and installing protective ‘hoops’ or ‘cages’ is helpful. However, as a well-intentioned farmer I am disappointed to see that the easier and more affordable solution overall is using pesticides.

With our end-goal being a farm to bar production of Organic Hawaiian Heirloom Chocolate we have begun our test of organic solutions to the Rose Beetle dilemma. Like most of you, I started my research on Google.

The HOT PEPPER SPRAY Recipe

The first organic pest solution we tried was The Hot Pepper Spray (HPS).  We found via Hawaii Organic Farming Association – whom referred us to this online pdf: Home Recipes for Pest Control via CTAHR.

This recipe didn’t answer all of our questions, so I contacted Daniel O’Doherty of Cacao Services Hawai’i.  

We decided on the following recipe and field application for our test.

 Hot Pepper Spray Ingredients 

  • 1/2 Cup Cayenne Pepper, Other Fresh Peppers (Habanero or Serrano)

  • 1 Gallon Water

  • 5-6 Drops of Dish Soap

Preparation Directions: Grind up all the peppers with water and dish soap using a blender, let it stand overnight, and strain it out with a cheesecloth or old piece of pantyhose. Wear gloves at all times while preparing.

Field Application Directions:
Test section pictured
Our Test Rows of Heirloom Cacao Trees are pictured here: the far two right rows of this ZONE of our orchard. (photo taken August 16, 2018 last day of test)

For use in the field, you’ll want to spray both the upper and lower sides of the leaves thoroughly. Make sure you’ve strained out all the small bits of pepper, or it may clog your sprayer. You’ll have to spray this regularly – at least 1-2x a week and after every rain because it is not an insecticide, but rather an insect deterrent/repellent. As with the preparation of the mixture, you will need to be careful during application. Definitely gloves, and likely a mask and goggles depending on the wind conditions.

Conclusion of HOT PEPPER SPRAY Field Test

HPS Spray Test Pau!

We sprayed 2 test sections 2-3x a week (our nursery with 50 seedlings and 2 rows of 1.5 yr old heirloom cacao trees  for a  period of 4 weeks.
We decided to stop the test because for our farm HPS is not a cost-effective solution to the Chinese Rose Beetle problem. We would love to hear from you if you have a different experience with HPS. Please contact us.

The Cons that we found for using HPS to repel Chinese Rose Beetles from Cacao:

  1. Our sprayer clogged continually and interrupted work hours. 
  2. Too much time spent straining the HPS with cheesecloth for the sprayer to not clog. We made batches of 3 gallons and considering our orchard needs 24-28 gallons per spray- this is not a good longterm solution. I could see it working for someone that has only a handful of trees and the time to make a DIY solution.
  3. Not effective solution for other pests: aphids and mealy bugs- as a result we switched from HPS repellent to an insecticide soap in the nursery. We began a new test with the brand SAFER. We are also considering hanging a light on a timer in our nursery for a CRB deterrent. However, lighting our entire orchard is not yet an option we are seriously considering.

Rose Beetle Damage on Cacao Leaf

Chinese Rose Beetle Damage

This is a picture from our spray test of new Chinese Rose Beetle damage while spraying HPS 2-3x per week. However, this was after rainfall event and there was minimal damage.

Hand Picking The Chinese Rose Beetle

Even though, this would not be our first choice. I have to wonder if the time and money we wold save in buying and spraying product would be worth it. We started to hand pick at the of August 2018.  We hand pick two hours after sunset and in some cases tap them into a jar of soapy water.

Organic Chinese Rose Beetle Control
Actual picture of our collection in one night (2 pickers over 2 hours)

This current field test- we will spray two rows with organic mix’ and leave the remainder with no spray. We will then observe to see if the CRB avoid either row of the sprayed trees.

Row 1: Neem Oil Peppermint Mix

Row 2: SAFER concentrate

Row 3: Hand Picking with no spray.

Whats Next on our Organic Field Test?

More resources:

An evaluation of several commercially available products for their effectiveness in reducing adult CRBs feeding and longevity: Management of Chinese Rose Beetle (Adoretus sinicus) Adults Feeding on Cacao (Theobroma cacao) Using Insecticides

Consulting of Daniel O’Doherty of Cacao Services Hawai’i phone: (808) 777-0548 email: info@cacaoservices.com  

Other Names: Chinese Rose Beetle, Adoretus Sinicus, Coleoptera Scarabaeidae – Chinese Beetle