Matted Mulch as an Alternative to Herbicide in Strawberries, Melons and Tomatoes

PROJECT BACKGROUND
Our operation is called Berry Best Farm. We raise everything from asparagus, strawberries, tomatoes, blueberries, blackberries, flowers, trees, sweet corn, to pumpkins in the fall. We do this on approximately 15 acres of ground from my father.

I have experimented with straw mulch and sawdust in strawberries, blueberries, blackberries, and tomatoes. Sawdust works well on blueberries and blackberries, but not on strawberries. Straw works on strawberries and tomatoes when winter or spring applied, but as this report will show, not in a pre applied fall application.

PROJECT DESCRIPTON AND RESULTS
Methylbromide fumigant is a major treatment for weed control in strawberries. This fumigant is being phased out by the Federal Government. Straw mulch has been used for winter protection and seems to suppress weeds.

In this project straw mulch was applied in the fall before strawberries, tomatoes, or melons were planted. In the spring strawberries were planted through the mulch. In the summer tomatoes and melons were planted through the mulch.

In the fall of 1996 straw mulch was laid. In the spring of 1997 strawberries, tomatoes, and melons were planted through the mulch. Machine planting was attempted, but finally hand planting completed the work. Spring 1997 was a very wet year, so much so that the results were thought to be inconclusive.

Dave Trotter, County Agent in Clark County, and Roy Ballard, County Agent in Floyd County, were very helpful in the design of this project. They both helped in locating and finally obtaining a rolled mulch called “bio-net” from an Evansville manufacture. “Bio-net” a rolled mulch, was used in the 1997-1998 trial along with straw mulch and black plastic. Again the straw mulch and bio-net were laid in the fall of 1997.

Tomatoes, cantaloupes, watermelons, and asparagus were planted in to black plastic, straw mulch, and rolled mulch. It can be noted from that four weeks after planting there is a notable difference in the various systems, with plants in black plastic growing much better. By the end of the season results were as follows:

Black plastic, straw mulch, rolled mulch
Tomatoes: 3 bushels, .7 bushels, .5 bushels
Cantaloupes: 1 bushel, -, -
Watermelons: 6 bushels, 1 bushel, -

Although all plots were fertilized equally at planting, there seemed to be a lack of plant vigor in both the straw mulched and the rolled mulched plots. In the previous year the experiment was run with strawberries on straw mulch and fumigated ground. It was noted that the strawberries planted into the straw mulch had very low vigor, but poor weather conditions were thought to be the problem. In light of the current results the poor plant vigor may be attributed to the straw mulch systems.

In 1998 strawberries were to be planted also, but asparagus was planted instead. The asparagus did quite well in all systems with the best growth in the black plastic.

The results of this project indicated that fall applied mulch probably removes nutrients from the soil. Winter and spring applied straw still seem to work, but now extra time, declined in vigor, and it would seem this may be due to the mulch and that fall applied fertilization could be a plus.

OUTREACH
Roy Ballard posted the project in his newsletter in the 1996-1997 experiment. A group of Washington County farmers, headed by Byron Fagg, extension educator/CED, came in the spring of 1997 to look at the results. The project was explained and a farm tour was given. It was very beneficial to all.

In January of 1999 my wife and I did a poster presentation at the Indiana Horticulture Convention at Indianapolis. Pictures and posters presented the results for all to see. A hand out was made to those wishing further information.

Through the two years the project ran, numerous people observed the project when they came to the farm to buy or pick produce.