The use of premium granular and water-soluble fertilisers is driving quality and yields for one of Western Australia’s largest suppliers of packaged salads, The Loose Leaf Lettuce Company.
Each week, the business delivers about 25,000 kilograms of fresh salad mixes to the Perth Markets and to wholesalers, who in turn supply food service channels throughout the city.
Owned by Barry, Maureen and Kevan Dobra, The Loose Leaf Lettuce Company was established in 1998 as a means of adding value to leafy vegetable crops grown on the family’s small market garden business at Lennard Brook, about 80 km north of Perth.
Production was significantly expanded with the purchase of a second property, ‘Sativa Gardens’ in 2005.
Today, the Dobra family grows a wide variety of leafy vegetable crops, including baby cos lettuce, red and green coral and oakleaf lettuce, baby spinach, wild rocket, Swiss chard, mizuna, and tatsoi under 52ha of fixed, overhead or pivot irrigation.
‘Sativa Gardens’ manager Jase Dobra says as a fresh food business, quality and food safety are paramount.
“There is no second-best when it comes to salad vegetables,” he said.
“Our customers demand a high quality, consistent product with no bruising, no leaf damage, no insects and a long shelf life, at least 10 days, and nutrition is a big part of that.”
Crops are fertigated six times a fortnight, alternating between NPK and UAN-based blends that are direct-fed into the centrally controlled irrigation system.
The NPK blend is based on YaraTera Kristalon water-soluble fertilisers.
These premium compound NPK formulations contain added micronutrients, such as boron, calcium, iron, magnesium, manganese, molybdenum, sulphur and zinc.
The UAN blend also contains various YaraTera Krista fertilisers to boost potassium, sulphur and magnesium content.
YaraTera Rexolin APN chelated micronutrients are also added to each blend to boost plant-available boron, copper, iron, manganese, molybdenum and zinc content as necessary.
“Our soils are like beach sand and don’t hold nutrients, so good nutrition is essential,” Mr Dobra said.
“As an all-in-one formulation, YaraTera Kristalon fertilisers makes things easier for us.
“We use the other Krista formulations to bring out the deeper colours in the plants or to help improve shelf-life, particularly during winter.
“YaraTera products dissolve quickly and completely in the blend tank and that means no blockages and no burn.”
High volumes of the granular compound NPK fertiliser, YaraMila Complex, are also applied every three days for the first three or four weeks of the crop cycle.
“We have used YaraMila Complex for as long as I can remember because it breaks down quickly with the water and doesn’t scorch the plants,” Mr Dobra said.
“It also stores well – nothing annoys me more than picking up a bag of fertiliser that has turned into a 25 kg brick.”
Most crops receive a pre-emergent application of a soil fumigant or herbicide, as well as a range of in-crop treatments to protect against insect pests and diseases.
Crop cycles vary from three to eight weeks, depending on the variety and season.
Crops are harvested using a specially designed harvester designed by Jase’s father, Kevan, and built by Garth Hindmarsh, a qualified boiler maker who manages the cropping operations on the Ashby Road farm.
It features a two-metre diameter scallop-toothed bandsaw that effortlessly slices leafy vegetable crops without picking up soil.
Three hydraulic elevators then rapidly convey the cut crop into a following tractor-drawn trailer loaded with 80kg bins.
Mr Dobra said the new harvester has slashed harvesting times and labour requirements.
“We can harvest ten 80kg bulk bins with two people in about four minutes.
“Before, it used to take five people 10 to 15 minutes just to harvest the crop, which increases the time taken before we can get it into the coolroom.”
On the flip side, three people are required to ‘decant’ the bulk bins into smaller crates back at the shed before consignment to the processing facility on the home property 20km away.
“We would rather have five workers in the shed than have them standing on the back of a trailer out in the paddock,” Mr Dobra said.
“Safety is paramount for everybody – but there are also important quality benefits because we are getting the crop out of the paddock and into cold storage sooner.
“Our ultimate plan is to redesign the decanting and loading process so that it can be handled by just two people.”
The Dobras’ previous harvester is still used to harvest cos lettuce, which needs to be packed directly into crates, and as a back-up for the new harvester.
Harvested produce is transferred to the processing facility at the Ashby Road farm, where it is washed, dried, weighed, mixed, bagged and packed into six different salad types.
The Loose Leaf Lettuce Company employs more than 60 permanent/part-time and casual staff working over two shifts, five days a week, including those working on the farms.
The company participates in FreshCare, an externally audited quality assurance system for on-farm food safety and quality, and as a food processor, HACCP accreditation for food safety and quality management.
The Loose Leaf Lettuce Company is an all-family affair, with Barry and Maureen’s four children – Kevan, Deanne, Simone and Peter – all actively involved in the business, as are several of their spouses and children.
