LIKE many growers, Kevan Dobra at Gingin in Western Australia has had a healthy scepticism for biological products.
That was until he discovered one on a United States field trip, returned to use it on his family’s property and has since seen land become productive again with strong plants, and which has also resulted in application savings and exceptional crop yields and quality.
In partnership with his parents, Barry and Maureen, Kevan operates The Loose Leaf Lettuce Company, growers and processors of fresh, gourmet salad vegetables.
They are one of the largest growers of lettuce, spinach and rocket in the State, while they also grow Asian greens, including kale.
Spinach crops are grown over about 24 days from direct seeding to harvest, while the lettuce is produced over seven to eight weeks.
They are irrigated twice a day using fixed irrigation and significant overhead irrigation, one of the only systems of its kind in Australia, while they are also fertilised thrice a week.
The spinach and green lettuce achieves yields of 16 t/ha and red lettuce produces about 8 t/ha, with all crops except for cos lettuce being machine cut.
Deliveries twice a day from the property go to Canning Vale Markets and other wholesalers and processors, as well as direct to clients.
Kevan said he was on a field trip to the US with David Gray and Co, viewing lettuce varieties in the Salinas Valley in California, when he heard about one of the latest biological products, Serenade Prime, during a visit to a Bayer manufacturing facility.
He said he was admittedly a little jaded before springing to life once he heard how the new liquid biological solution colonises plant roots and ameliorates soil resources for the crop.
Serenade® Prime contains viable spores of the highly active QST 713 strain of beneficial bacteria Bacillus subtilis.
After germination, these beneficial bacteria live on plant root surfaces and in the soil zone around the root systems, called rhizosphere, where they can develop mutually beneficial relationships with plants under suitable conditions.
When interactions between the bacteria, plants and soil are balanced, both the plants and bacterial populations function at a higher level, allowing nutrients and water to become more available.
In short cycle crops, Serenade Prime is designed to be used early as an inoculating agent, while in perennial crops, it is designed to reinvigorate the soil/root/microbe relationship at critical growth times.
At The Loose Leaf Lettuce Company, dolomite is applied at 1t/ac in preparation for crops and in the spinach, Serenade Prime has been boomspray applied just after seedling emergence at 7L/ha, followed by a similar application in a further seven days before harvesting a week later. Each application has been followed by a 5mm irrigation.
Kevan said the second application of Serenade Prime would be delayed during the cooler months, when the growing period is extended by three weeks.
He said application timing was the key and in the lettuce, they don’t carry out an early application.
They wait for plant roots to become a decent size before applications in week two and four prior to harvesting in weeks seven to eight.
“To be honest, if we didn’t have this (Serenade Prime) this season, we would have had to get someone else to grow for us,’’ Kevan said.
“When we first started using it, we continued injecting metham sodium five days before seeding and then used the Serenade Prime. Then we saw no difference by just using Serenade Prime by itself.’’
He said since the Serenade Prime applications, plants were looking really good.
“In the spinach, the roots are whiter, healthier and they are going deeper – and this will be better for the roots to get calcium, particularly when things are slower in winter,” Kevan said.
“Plants are absorbing nutrients quicker and we are not putting calcium through the water, as we would normally do in summer.
“Water here is very good (with a Mount Franklin site nearby) and every week we apply 100-120 L/ha of calcium and boron, so we are saving 500 L/ha over the whole crop.
“We are also seeing less burn in lettuce.’’
Bayer customer sales representative, Jim Brussen, said the use of Serenade Prime in crops was producing robust, stronger plants that also matured quicker.
Kevan said he was most impressed with the biological product.
“I don’t believe in biologicals,’’ he said.
“I’ve done about 100 Seasols, composts and trichodermas, so this was an eye-opener.
“It’s good stuff. There are other products out there, but they don’t do what Serenade Prime does.
“The crops and the quality are exceptional – and there’s no withholding period, so we can harvest immediately.
“We are saving $700/ha in metham sodium. We are also saving $500/ha in calcium. We had bought a mouldboard plough and had started mouldboarding to combat the soil issues as well.’’
Des May, with David Gray and Co, said there was strong interest in biological products and Serenade Prime was showing promising results in several crops, with better root systems and stronger plants.
“It’s also a good, affordable product, which is great,’’ he said.
- Copy courtesy Bayer Crop Science.
