Lettuce is beholden to an inconsistent market, with demand usually depending on the climate. Sustainable manufacturing subsequently requires cautious administration of provide and demand. Equally necessary, as farmer
Jakkie Mellet defined to Lindi Botha, is a shorter, extra productive, progress cycle.
Picture: Lindi Botha
Sterkspruit farm, close to Lydenburg in Mpumalanga, is located on the very prime of Lengthy Tom Cross, 2 150m above sea stage. Its place holds important advantages for proprietor Jakkie Mellet: it’s remoted from different farms, protecting it comparatively secure from the potential unfold of pests and ailments, and it’s usually wreathed in mist, which creates a microclimate best for the farm’s potato seed manufacturing.
Alternatively, the rocky nature of the land, being on the mountain prime, signifies that solely a fraction of the property may be cultivated.
Confronted with this dilemma, Mellet sought different crops that would complement his potato seed operation. Cherries, berries and kiwi fruit have been all thought of, however solely the final was possible. Then, three years in the past, he was approached by Woolworths to supply lettuce through the hotter summer season months, when many of the retailer’s standard suppliers round Gauteng cease manufacturing.
“Lettuce is a cool-weather crop and it likes gentle summer season temperatures,” explains Mellet. “Farmers who sometimes ship to Woolworths can sustain manufacturing in winter, however the summers are too sizzling, because the lettuce bulks up and begins to seed.
“Local weather performs an important function in lettuce manufacturing, and it simply so occurs that the local weather for potato seed manufacturing can also be suited to rising lettuce: excessive altitude and excessive rainfall.”
Sterkspruit has annual rainfall of 950mm, principally in summer season. Summer season temperatures peak round 30°C due to the farm’s place on prime of the mountain. Furthermore, the chilly air travels down, protecting the evenings heat sufficient for manufacturing.
“Though the realm will get frost, the lettuce doesn’t appear to thoughts. The leaves may be coated in frost within the early morning, and by the point the solar is out, the frost is gone and the crops simply proceed as regular.”
Mellet notes that whereas winter manufacturing is feasible on the 19°C day-time common, it’s not worthwhile. “The cycle extends from six weeks as much as 10 weeks, which is simply too lengthy. It doesn’t make financial sense.”
Manufacturing
Mellet’s lettuce season runs from the center of October till the top of Could. The manufacturing cycle takes seven weeks early within the season, and averages six weeks as soon as summer season is in full swing.
A draw back of the Lowveld local weather is the prevalence of hail.
“It’s not if, however when and the way a lot hail we get in a season. This is likely one of the causes we plant the lettuce underneath a hail web, in luggage stuffed with sand. We run a hydroponics system, and the sand is there simply to maintain the crops upright within the luggage,” explains Mellet.
The lettuce manufacturing cycle begins with seedling manufacturing. That is dealt with in devoted services on-farm underneath the experience of the potato seed manufacturing group. With the ability to produce their very own seedlings can also be a price saving, because the transport prices of seedlings to this remoted farm can be prohibitive.
Some 75 000 seedlings are produced every week. The seeds are planted by hand in trays stuffed with a compost combine, then saved in a temperature-controlled room at 18°C for 3 days to germinate. They spend three weeks within the nursery and one other week out within the open to harden earlier than being planted within the 3ha rising space. A complete of 342 000 seedlings of 11 varieties are planted, and this produces 25t/ha each six weeks.
Lettuce manufacturing has a excessive labour requirement, and Mellet employs 18 everlasting employees. Weeds are a significant concern, as they need to be eliminated by hand. To cut back this drawback, a weed mat is used within the rising space, and this, in accordance with Mellet, cuts the labour element by two full-time employees.
All water and vitamins are supplied by way of an irrigation system that administers eight pulses a day. Every bag has its personal dripper, dishing out round 7mm of water per pulse and 56mm/ plant/day. The water’s electrical conductivity (EC) is measured when the water goes into the bag and once more when it runs out.
Mellet explains that the EC ought to at all times be decrease within the water seeping out of the bag; if it’s not, salt is build up within the bag. To forestall this drawback, the baggage are flushed each day with clear water to take away any extra salts. Rain gives this flushing motion throughout summer season, so on wet days the guide flush may be skipped.
Mellet says that adhering to the irrigation schedule is essential and a generator has subsequently been put in for durations of load-shedding.
Trial, error and success
Lowering the time to reap is a vital ingredient in worthwhile, sustainable lettuce manufacturing, in accordance with Mellet. He and his workers continuously use trial and error to search out the optimum recipe.
“We’ve tried many issues through the years and have landed on a formulation that offers us good outcomes. However the actual fertigation recipe for the most effective manufacturing continues to be a thriller.
Producing lettuce is a little bit of an artwork. Merely rising the crop just isn’t tough, however to take action profitably, and get a constant turnaround of six weeks or much less, is hard. Every grower has his or her personal commerce secrets and techniques and is reluctant to share this aggressive benefit!”
One change being applied on account of their trials is a swap from compost to a coco peat combination within the nursery. It was discovered that utilizing the latter initially of the rising course of diminished the time to reap by between seven and 10 days.
Though the coco peat combination is extra expensive, it has solved the bottleneck skilled on the farm between planting and harvesting.
“As soon as the seeds are planted, it’s a four-week wait earlier than they’re prepared for planting out. With a weekly planting cycle, this implies almost 1 200 trays taking on area. Lowering this ready time by every week means fewer trays, and I save a whole week of administration and inputs. That provides as much as fairly a big sum.”
The farm has additionally switched from white to black seedling trays, because the latter take up extra warmth and cut back the rising time.
“Within the salad sport, it’s about turnaround, so the quicker you may get the product out, the decrease the manufacturing prices,” says Mellet.
Sterkspruit’s nursery supervisor Werner Schutte does his bit to cut back rising time and price by fine-tuning vitamin. To this finish, he makes use of organic merchandise so far as doable to assist soil and plant well being.
Schutte had a current breakthrough when he found a brand new formulation containing a nano-fertiliser. This product ends in a considerably greater uptake of vitamins within the crops, and has led to a dramatic discount in seedling manufacturing price from R0,60/seedling to R0,06/seedling.
Whereas he’s reluctant to disclose the precise specs of the product, Mellet says it comprises a spread of helpful fungi and micro organism that support plant well being and drastically enhance nutrient uptake.
The drive to maneuver away from harsh chemical substances is hindered by the dearth of a organic answer to forestall biofilm from build up on irrigation methods.
“I’ve to flush the pipes with hydrogen peroxide after each cycle to maintain them clear, and this kills all of the helpful micro organism and fungi. So with each cycle, now we have to start out afresh to construct them up once more.”
Mellet provides that the isolation of the farm means there’s little illness strain, with only some incidents of white lice once in a while.
“We diligently comply with the Farming for the Future and GlobalGAP pest administration programmes, scouting after which spraying solely when mandatory. However there are some points which can be higher dealt with with a set programme, as a result of the chance of injury is just too excessive to take an opportunity.
“Complying with all of the regulatory our bodies can flip right into a paper battle, however a lot of it’s simply good agricultural practices that must be in place anyway.”
Harvest
A lettuce grower has to maintain a eager eye on the temperature and chilly chain at harvest time to keep up optimum freshness and an extended shelf life.
“If it’s going to be a very sizzling day, we begin harvesting at 5am, then cease at 11am, and restart at 3pm. It’s solely 1km from the land to the chilly room, however even alongside this quick distance the lettuce can wilt if the temperature is just too excessive. With lettuce, one thing as seemingly insignificant as this may have an effect on high quality.”
The lettuce is reduce off above the roots when harvested and the roots are left within the sand. The brand new seedling is then planted subsequent to it. Mellet goals to make use of the identical soil for 2 years earlier than changing it, and eradicating the complete root would consequence within the lack of an excessive amount of sand. Earlier than the brand new seedlings are planted, nonetheless, the baggage are sterilised with a hydrogen peroxide answer by way of the irrigation system.
As soon as the lettuce has been reduce, it’s positioned in lug packing containers and despatched to the chilly room on the farm. A transport contractor collects the produce two or thrice every week, protecting the temperature at a relentless 8°C. As soon as the lettuce is acquired on the Woolworths packhouse, it’s reduce up, washed and sorted.
Sterkspruit farm is round 300km from the Woolworths packhouse, and transport is Mellet’s biggest expense. Nonetheless, utilizing a contractor eliminates a lot of the pressure that might go along with managing a transport fleet himself.
A balancing act
Having to deal with the vagaries of the lettuce market is by far Mellet’s greatest total problem. He’s anticipated to fulfill larger-than-anticipated portions, in addition to handle extra manufacturing when the demand unexpectedly drops.
“We solely produce on order, however this may range fairly a bit. At the start of the season, when individuals are not consuming that a lot salad but, we produce about 8t/ week, and this goes as much as 16t/week over Christmas and the height summer season months.”
Mellet has blended emotions in regards to the market. “Lettuce just isn’t an amazing commodity to be in when the financial system is underneath strain, as a result of it’s the very first thing individuals cease shopping for. It’s not a staple meals, and comprises no protein and never a lot of dietary worth. It’s a nice-to-have. Though there’s a section of the inhabitants that’s rising in affluence and we do see potential for some progress, demand fluctuates.
“The climate performs an enormous function. If it immediately will get overcast and the weekend braais are cancelled, salad gross sales drop. I’ll ship 4t in the future and 2t the day after, as demand drops.
It’s a really tough market to be in. However when it goes properly, we smile. We’ve made peace with having to feed a sure portion of manufacturing to our cattle.”
Mellet goals to cut back the variety of leaves wasted on the packing stage due to blemishes or wilting. “Round 60% of what we produce is discarded through the packaging part. Producing underneath a web helps, however we have to go additional.
“To stay sustainable, we have to guarantee larger effectivity, and put out a heavier head of lettuce utilizing much less time and fewer inputs. By higher administration of all of the steps alongside the way in which and all of the inputs, we are able to make beneficial properties on this regard. We’re continuously looking for higher, extra environment friendly methods of manufacturing better-quality lettuce that matures quicker.”
E mail Jakkie Mellet at [email protected].
