PHONG Nguyen is employing a range of techniques to improve and grow his vegetable seedling business on the Northern Adelaide Plains in South Australia, as well as for his own hydroponic tomato production, and his latest move is getting the “thumbs-up’’ from grower customers.
Phong and his wife, Anne, run MNV Nursery near Virgina, one of three nurseries in the area supplying the region’s 700-1000 growers.
Established in 2007, the nursery turns out eight to 10 million pre-ordered cucumber, tomato, capsicum and eggplant seedlings, while they are in their third season producing 35 kg/m² of hydroponic tomatoes over 4500 m², and which finds homes as far away as Queensland and Sydney.
Phong said he was moving toward a more sophisticated seedling system and, hence, was adopting a number of practices.
This has included grafting from rootstock, which has also required a separate hygiene system, to produce better plants with higher yield potentials and improved disease profiles.
A heating system is used in winter to help fast-track seedlings. Capsicums are ready in two months, while tomatoes are available in four weeks and cucumbers take 16 days.
Phong built his hydroponic system and previously fertigated every day into the vermiculite and peat moss media with six different custom mixes injected from four tanks, and using reverse osmosis water.
The different mixes included potassium nitrate, calcium nitrate, magnesium sulphate, potassium sulphate, monammonium phosphate, boron, calcium, iron, manganese, molybdenum and zinc.
He said since late last year, he had been applying the new biological solution, Serenade Prime from Bayer, every two weeks.
Serenade Prime contains viable spores of the highly active QST 713 strain of the soil ameliorating beneficial bacteria Bacillus subtilis.
After germination, these beneficial bacteria live on plant root surfaces and in the zone around the root systems, called the rhizosphere, where they develop mutually beneficial relationships with plants under suitable conditions.
When interactions between the bacteria, the plant roots and the soil or root media 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.
Local Bayer commercial sales representative, Darren Alexander, said the big advantage with Serenade Prime was that the QST 713 strain was highly consistent.
“The bacteria can colonise the roots in as little time as 24 hours and live off the exudates from the roots. As long as the roots are growing, they can be colonised,’’ Darren said.
“In return for the root exudates, the Serenade Prime QST 713 bacteria ameliorate soil/media resources, making key nutrients more available to the plant roots.’’
He said leaf tissue testing had shown the benefits of Serenade Prime for root development and nutrient uptake.
“It is important to know that plant roots can only take nutrients up in the liquid form, so soil moisture is important for nutrient uptake,” he said.
“If Serenade Prime changes the soil nutrients into more plant-friendly forms, which in turn supports a stronger, healthier, larger root system, then the plant has the ability to grow closer to its potential with less environmental limitations.’
“In our plant tissue testing, we are seeing higher levels of micro nutrients in plants treated with Serenade Prime.’’
At MNV Nursery, seedling trays are dipped in a solution containing Serenade Prime before making further applications of a seaweed product. Dependent upon weather conditions, a root feed stimulant is also used.
“We have seen the benefits of a stronger root system,’’ Phong said.
“Our customers are saying the (Serenade Prime-treated) plants are healthier, with more root hair in the seedling cell, so they have also noticed the good result with Serenade Prime.
“All plants have gone out and all customers have said they are perfect.’’
The system is thoroughly cleaned with chlorine every two months.
Darren said one of the best times to use Serenade Prime was immediately after sterilisation, to allow root colonisation in clean media.
Phong said following the good feedback from grower customers, he had since been using it in his hydroponic tomatoes once a month over the 10-month growing period.
“There is more root development and whiter roots compared with last year, when I used a different product. It’s also made the plants healthier and stronger,’’ he said.
“This has also been with ungrafted plants. If we were using grafted plants, this root development would be normal, but compared with other ungrafted plants, this is far far better.’’
At $142 per 10 L drum, Phong said he was advising growers to use Serenade Prime rather than other products.
- Copy supplied by Bayer.