Next week, on Wednesday, February 11, we’ll be holding our next mummy berry workshop in Mt. Vernon, Washington in affiliation with the Northwest Center for Alternatives to Pesticides.
In anticipation of sharing ideas and research regarding blueberry production and mummy berry control, I’m answering a recent inquiry I received as a blog post. It regards the control a mummy berry using Visqueen, which was discussed at the field day we held last June in Alvadore, Oregon.
Disclaimer: This method of disease control has never been scientifically tested and we have no evidence, other than reports from one farmer, regarding its efficacy. This information is shared in hopes of facilitating information exchange between farmers and to provide ideas of how management techniques can be used together.
Here’s the inquiry:
Hi Jade
My wife and I have an small organic Blueberry farm . We are interested in the system Ken Berg uses to manage mummy berry.
We would like to know how early people are putting down the Visqueen plastic for this season. We have had a mild winter here, and assume we would have to be ready pretty soon.
How wide are the strips of plastic – how far into the row middles from the plant does he place the plastic, or is it all the way across the rows. We have grass row middles, and there are probably some mummies in there, although we tried to mow and “vacuum” with our mower as close to the ground as possible during the fall clean-up.
We also picked up all visible mummies from around the plant – but we are never able to get them all.
Would it be possible to be on your email list, and to receive any new information that you may have through your research on organic Blueberry production?
What are the weights/sizes for Visqueen that are appropriate for this purpose? And would we find them in greenhouse supply outlets, or is there a special supplier?
Any answers you have would be very helpful, and much appreciated.
Thank you.
Response:
Site Description
Ken Berg’s operation has been in production since 1990. It is mostly a U-Pick operation with fresh market and some frozen market. He conducts only on-farm sales. He has 20 rows of blueberries, including the varieties: Draper, Chandler, Blueray, Spartan, Collins, Liberty, and Patriot. He also has netting to protect fruit from birds.
Site History
Berg began to worry about mummy berry in 2010, when he had an 83% crop loss. After that, he raked the whole farm, disposed of debris and mummies in barrels, and hauled them off. The next year (2011), he had 87% crop loss due to mummy berry. At, that point he decided to use another technique. Berg then developed a system to create a protective barrier between mummy berry apothecia and his blueberry plants.
The Visqueen-Mulch System
Image by Jade Florence. Ken Berg pointing to the area where the Visqueen sheets meet in the middle of the row.
How and when is the Visqueen laid down? When are the blueberries mulched?
In early February, Berg begins to put Visquene plastic down after mulching the crown of every blueberry bush. The Visqueen sheet should be laid down along the blueberry row, between the aisle and the base of the blueberry bush. The two pieces of Visqueen on either side of the row should meet around the blueberry crown. Then apply mulch around the edges of the Visqueen to hold the plastic down (See above picture).
According to a communication with Bernadine Strik, a berry crop specialist in the Department of Horticulture at Oregon State University:
Weed mat or landscape fabric controls weeds well, but [you] must have a drip irrigation line under the weed mat or the plants may not get watered well enough.
Hence, this system is better adapted to systems with drip irrigation in place. Leave the Visqueen-mulch combination down until the end of the flowering period – which is generally around the end of May in the Pacific Northwest. When you’re ready to remove the Visqueen, spend time as carefully as you can, removing the Visqueen and storing it away for next season. If you handle the Visqueen with care and have a “high mil” Visqueen (see below), then your Visqueen should last for multiple seasons.
How often is the Visqueen replaced?
Berg spends a total of $600 on a >1 mil Visquene plastic (including freight delivery) and reuses it for multiple years (>2).
If the Visqueen is 1 mil or less, it may only be useable for one year.
How wide are the strips of plastic/ How far into the row middles from the plant do you place the plastic?
The plastic goes from the edge of every alley to mid-row and joins in the center between the bushes. So if you measure that width, you should be able to find the width of Visqueen needed.
What are the weights/sizes for Visqueen that are appropriate for this purpose?
Find as heavy of a “mil” weight Visqueen as you can find! Berg has used a mere “1 mil” weight in the past and was only able to use that Visqueen for one or two seasons. With a higher weight Visqueen, the plastic is more durable.
And can the Visqueen be found in greenhouse supply outlets, or is there a special supplier?
Berg orders from Robert Marvel Plastics in Philadelphia. That is where he has found his best deal for the most product. Locally, there was no one who could supply the amount he needed at a price he could afford.
Sorry, but 25 and 50 foot rolls, is not gonna do it for me, when I needed 8,000 ft of material! -Ken Berg
And as for his take on his mummy berry levels…
It is phenomenally diverse. From an all time high of 87% loss, down to about 10% in two years time. Last year, due to turkeys tearing up large sections of the Visqueen, it jumped up to approximately 34% this last berry season.
Take Away Points:
- Start pruning as early as possible. Berg recommends starting in November.
- Order your Visqueen in December-January and have your mulch ready
- Begin the Visqueen-Mulch System in early February
- Pull back the previously laid Visqueen (or if this is your first year, keep Visqueen set aside) and mulch the blueberry bushes with Douglas fir sawdust to about 2 inches.
- This year, Berg wanted to encourage worm activity, so he is also adding in a compost into the mix.
- Mulch the entire row, on both sides
- Then, starting with one side of the row, begin laying down the Visqueen plastic over the sawdust and/or compost mixture.
- Plastic should reach from the edge of every alley to the mid-row and join in the center between the bushes.
- To secure the Visqueen in place, use additional mulch added on top of the Visqueen, along the edges of the plastic.
- Repeat this on the other side of the row
- Pull back the previously laid Visqueen (or if this is your first year, keep Visqueen set aside) and mulch the blueberry bushes with Douglas fir sawdust to about 2 inches.
- Pull back the Visqueen after all the blooms are gone/done, or the vast majority anyway – which is generally around the end of May. This will allow mummies to naturally drop at harvest, so they can be covered again the next February.
So there you have it! The quick and dirty synopsis of the Visqueen-Mulch System. But since there’s interest in this system, I’m looking into creating a how-to video and more footage of this practice taking place.
My goal in running the OSU Mummy Berry Blog is to encourage information exchange and partnerships between growers. I coordinate grower meetings, not only to provide a platform for sharing my own mummy berry research, but to highlight methods that farmers in the region have used, and to discuss new ideas. If you as a reader have ANY information you’d like to hear about, whether it regards controlling mummy berry, or blueberry production in general, please don’t hesitate to write a comment, or email me directly.
– Jade Florence
