We’re covering this extensive story in two parts so, if you’ve ‘just joined’ you might want to go back and catch PART 1 first.

Here’s PART 2:

FARM CONTEXT
Date of visit	13 September 2022
Area	Levubu, Limpopo (Farms in Levubu and Piesanghoek)
Soils	Mostly Huttons. Generally 10 to 30% clay content.
Rainfall	Piesanghoek: 7-year average is 1250mm. Springfield: 850mm annually.
Altitude	750m – 1300m
Distance from the coast	Over 400kms
Temperature range	Record high – 43°C (Jan). Average high 31°C (Nov) Record low – 3°C (June). Average low 9°C (June)
Varieties	Fuerte, Hass, Ryan, Gwen, Lamb Hass, Pinkertons, Edranol, Reeds.
Hectares of Avos	182.15 ha (146.24 ha in production).
Diversification	Avos: Nursery, Packhouse and Partners in an Export Business. Macs: 267.19 ha. Also Nursery and Processing and Marketing Company. Pecans: 79.01 ha. Shareholders in a Processing Company. Timber: 850ha (Gum)

In PART 1 we covered:

• Getting to know the JAFFs
• Avo history and getting started
• Markets
• Development Planning
• Land Prep
• Nursery
• Planting
• Soil Health and Nutrition

We continue with:

ORCHARD REJUVENATION

We’ve mentioned transition and rejuvenation a few times – these are prominent topics in Levubu right now. As the birthplace of the macadamia industry, they have had to learn everything the hard way, with no one being able to supply the evidence as to whether what they were doing was right or wrong. Turns out, pruning is important and insects are a thing. (That feels like the biggest understatement we’ve ever written! ) But, a few years on, we have the privilege of perspective and learning. It still doesn’t make cutting your massive macadamia tree down easy. In fact, I know farmers who chose to leave the property when their trees are being pruned.

This farm has learnt that avos also need to be restrained and now go by the motto: “If you can’t harvest it and you can’t spray it, we can’t farm it.” ie: if it’s too high to harvest or spray, it’s not farmable. Harvesting is R1 more expensive (per kg) for every metre higher you go. Nutrition is more expensive because you’re feeding huge trees that are only productive on the outside. Spraying is less effective, and more expensive, on big trees. Wind damage is worse. There’s simply no good reason to farm big avo trees … so the JAFFs have embarked on a two-pronged orchard rejuvenation programme:

1. Cut back. A few years ago they started bringing the trees down, one large limb at a time. It hasn’t been pretty but the trees have responded remarkably, as have the results.

This 58 year old fuerte orchard has been rejuvenated through pruning, injecting and fertilising. The inside of the tree is already filling up with vigorous new growth and will produce a good crop next year.

A few purposeful cuts have already been made here; more to come.

Note all the new growth, heavy with flower, that this old tree is sustaining. You can almost feel the sigh of relief in these rejuvenated orchards.

The pruned wood is all left in the orchards to enrich the soil.

This orchard was Fuerte and then, many years ago, top-worked to Hass. In cutting back they had to be careful not to cut back too far otherwise they’d get back to Fuerte. It had gotten so tall though that harvesting was being done with a cherry picker!

One of these ‘harshly pruned’ orchards was yielding 8t/ha before the ‘big chop’. The next season it came back with 11t/ha AND it was more efficient to harvest, with better quality fruit (minimal damage). Next year the estimate for this orchard is 15t/ha.

2. After-the-fact ridging

The second part of this orchard rejuvenation project is amazing. JAFF advises that you use it only as a last resort, at this early stage, as very few people have done it. It seems to have originated with a farmer in the area who was advised to start over in an orchard that had never been ridged and was struggling with soil issues … and this time he should ridge. Figuring he had nothing to lose, he asked, “What if I ridge now?” Despite the (expected) gaping mouths, he decided to do just that. The orchard turned around and he shared the success with others … JAFF has a similar orchard and decided, he too, would give it a go, “We weren’t risking much, besides bulldozer time.”

Yes, we are suggesting that you try ridging a mature, unridged orchard, IF you are out of other options. This is done by deep ripping the interrow and then bulldozing the loosened soil under the trees. At this point JAFF put in some kraal manure and left the prunings around the base of the trees. They then came in with spades to close off and shape the ridges. JAFF says they have tried, as much as possible, to keep the soil off the tree stems but, where it has happened, the trees don’t seem to have minded.

Their first ‘after-the-fact’ ridging exercise was done 3 years ago and they’ve since done it on 15- to 38-year-old orchards – all have shown incredible improvements and, together with the large limb pruning and height reduction, they’ve returned these orchards back into profitable production.

An added benefit is that, in sick orchards like the ones you’d consider this for, there are often many gaps; the new ridges are perfect for planting new trees in these spaces.

After-the-fact ridging Step-by-Step:

1. Supplement the root zone with whatever organic matter or nutrients you’d like to close into the ridge.
2. Deep rip the interrow.
3. Push the loose soil under the tree canopy.
4. Use spades to shape the ridges around the tree stems.
5. Rehabilitate the vegetation in the interrow.

Step 3 of the ridging complete. Next is to use spades to shape these ridges. JAFF has left them open for the dry season as they have been beneficial reservoirs. They will be closed before the rain starts at the end of October.

This pruned wood will be closed into the ridge – imagine the soil life that’ll thrive off this feast.

A peek over the edge. These are Hass on Velvick trees. Because they’ve been stressed, the pruning strategy here is slightly different – the focus is on opening up rather than on bringing the height down at the moment.

A good illustration of what happens if you work bulldozers in soil that’s too wet. JAFF explains that this compaction is easily avoided by working the soil when it’s drier.

JAFF can’t believe the positive change the ‘after-the-fact’ ridging has made – When I arrived on the farm, an orchard had already been ‘after-the-fact’ ridged’, and the health of it compared to the neighbouring block was very evident. “So, we decided to roll this out to aged blocks stressed from phytophthora”.

 PRUNING

Apart from the orchard rejuvenation programme that entails aggressively removing large limbs and dropping tree height by many metres, there’s also ongoing pruning that will prevent the need for any drastic interventions.

The JAFFs explain that the timing of the annual prune is crucial – if it is done too early, the trees will push vegetative regrowth. It needs to be done when the tree is ready to flower so that it pushes flowers out, instead of leaves. For these farms, May, June & July are pruning months; after flower initiation has started. JAFF explains that they prefer the trees to have entered winter dormancy stage before pruning starts. It’s definitely different to the more common strategy of pruning straight after harvest but the logic is sound.

In terms of strategy, they focus on height, light and rejuvenation; “same as a mac tree,” says JAFF, “promote horizontal growth and encourage as much sunlight into the tree as possible, keeping the trees low, open and flat.” (Mac pruning differs here, complicated by the need for a central leader) With avos, it’s important to try and encourage fruit INSIDE the tree where it will be protected from the sun and the wind, and flowers more accessible to insects for pollination.

A clover-shaped pruning, to open up critical windows, works well in widely spaced blocks. But when spacing is dense, a 3-finger approach usually works better. For the latter, it is important to keep coming back every year to remove one of the fingers as new ones mature to take its place.

JAFF says you can’t really start shaping an avo tree before year 3 or 4. Unlike a mac tree, if you tip it, it won’t generate multiple shoots, it’ll just grow a replacement shoot and carry on straight. So, when they reach about 4 years old, you start to control the upright growth; here they do that through a limb removal programme; taking out anything that blocks sunlight to the inner space.

Branches are bent and manipulated as a part of summer regrowth management; potentially productive branches that are growing upwards will be redirected sideways – they do this by simply bending, or tucking the branch behind or under another one so it is held in place.

“More sunlight into the middle of your tree means that it will flower and set sooner,” explains JAFF, “the pest pressure is reduced and you might even reduce the stress of the real hot months, which is important here, where the hot, dry weather in October-November can cause significant flower or fruit damage.”

Avos are prone to sunburn and exposed branches must be protected within 24 hours of pruning. Here, they focus on the northwestern-facing side of the tree which catches the hot afternoon sun.

These paint machines are used, together with knapsacks and spray guns, to apply paint quickly and efficiently as soon as possible after pruning.

As far as skirting goes, the resident bush buck do all the skirting that needs to be done (and more!).

Pruned wood is left in the orchards; unchipped for now, but JAFF says chipping it would be ideal. “We only have one chipper and we struggle to get around the entire mac and avo farms chipping, however we do mulch the rest of the pruning’s with a side discharge mulcher.”

IRRIGATION & DRY LAND

There is a lot of dryland farming in this operation; made possible by the high rainfall levels. Apparently, this is one of the highest rainfall areas in the country – Entabeni, a forestry area close by, has an average of 2500mm per year. So all irrigation is purely supplementary and, this year, they only started the pumps at the end of July.

Piesanghoek high rainfalls: The closer you get to the mountain, the wetter it gets because the cold fronts come through, whip up against the mountain (which is one of the few in our country that runs east west as opposed to north south) and gets ‘stuck’ in the horseshoe shapes – as a result it rains for days!

And that’s why dryland avos and macs can be sustainably and profitably farmed here – the Piesanghoek farms more so than the Springfield ones, which are further from the mountain. Despite this, they still plan to put irrigation in throughout so that they can get through those critical periods without stress. We must confess, we thought this a little ‘extra’ but JAFF explained that, if you hit a dry year and don’t have irrigation, your yield can halve. That alone would justify the investment.

Irrigation is installed before the trees are planted, if it’s an irrigated development. Dry lands are watered once a week in the dry seasons for the first 2 years.

Currently there are 83 ha under micros: with the balance of the 180 ha dryland (so, it’s roughly half-half). The micros are set to deliver 58l/hour, with one micro per tree (except for the very big, old trees that have 2). Most of the water comes from boreholes but on the Piesanghoek farms most of the irrigation is done from the river.

This 43-year-old Fuerte orchard has 2 micros per tree because of the size of the trees.

With the scope of their anticipated developments they need to be cautious about water use. Even though they stay under their allowances, surface water allocations are very difficult to get, and boreholes become the only other option.

Looking to the future, drip irrigation is definitely the preferred option because of the reduced water and electricity use, the opportunity to fertigate with precision and the fact that high clay soils are healthier under drip; the increased aeration minimises phytophthora outbreaks. All these factors would allow them to open up more developments sustainably despite the higher cost of the initial installation.

Current developments are getting drip systems; 2 drip lines per row, 0.7l/hour with a 1m spacing. GPS-linked probes providing updates every 20mins.

JAFF points out that the precision they are after can only be achieved with computerisation because of the inherent complexities. Fertigating 100 hectares, precisely what each hectare requires, at once, is not possible without low flow drip technology; especially when you want to scale while keeping management and labour interventions low. The strategy is to stretch the water, fertigate properly, have more control and less reliance on humans … all in a high clay environment.

It’s scary to accept that the future includes irrigation software that manages moisture without you. JAFF says there’s an apple farmer in the Western Cape who hasn’t touched anything manual in 3 years; the system assimilates soil data and weather data with crop info (age, cultivar, spacing etc) and turns the pumps on and off itself.

Healthy dryland soils showing vigorous root growth and an earthworm!

PEST MANAGEMENT

Being a mac and avo farmer seems to induce a situation of 1+1=3 when it comes to pest management. It’s as though the mac pests suddenly wake up to the fact that there’s bigger, softer fruit available and they can hop on over to that for diner if they’re feeling unwelcome in the macs.

Thrips is a big culprit and many avo farms, that have been pesticide-free, are finding themselves considering the option – this farm included. The avo orchards alongside the macs are particularly hard hit so it’s definitely related to the macs. As another mitigation, they are also starting to separate the crops as much as possible and making sure there is an ecological corridor running between them wherever possible. Hopefully this will encourage natural predators and introduce alternative food sources – especially for the 300+ beehives on the farms.

Really small green skin avos are top of the thrips menu and their feasting scars the avo for life, relegating it to second grade in the local market; a big financial hit for the farmer. Absolutely nothing wrong with the fruit inside, but international consumers prefer their avos perfect inside and out.  

A similar mix to the interrow cover crop is used to build up ecological corridors throughout the farm. This one surrounded a new mac field and also had Albizias (Flat Crowns) that had been recovered from the pine plantation we were developing and relocated to the edge of the new developments.

The JAFFs have tried the mites, a biological solution for thrips, but it seems that they can only eat so much and they haven’t managed to make much of a difference. Whilst I was visiting, Elsje Joubert was doing some biological trials and the JAFFs report that the conclusion was that Metarhizium, boveril , Beauvaria and bioneem are proven to be effective in thrip and sucking bug control. “We have started the season with our first Metarhizium spray for sucking bugs, but await effectivity results,” is JAFF’s latest update.

Not only are both JAFFs committed nature lovers, JAFF 1’s wife has a doctorate in Environmental Science so we can rest assured that no one is going to be shooting from the hip with unnecessary pesticides before they’ve exhausted every other option. Mrs JAFF’s final thesis was on bats and birds as natural pest control in macadamias – how handy!? But, they believe that biological controls are not a silver bullet, but rather another string to the guitar, where the more it is encouraged the better the balance all round.

Double-sided bat hotels (a cool side and a warmer option on the other side) sprinkle the farm.

The bats do support in controlling the seasonal pests which is a continuous challenge, however we are hopeful that our combination of biological controls and sprays have the results we are hoping for.

Coconut bug damage

There are 6 full time scouts in this operation, covering both macs and avos. In the avos, all scouting is visual (no chemicals involved); the scouts inspect 30 trees per block (the 4 corners plus a few random spots in the middle). Every block is inspected every week and the results recorded using GPS points and a special App. What we found key was that they are also recording the beneficials. This is important because the decision can then be made as to whether Nature has the situation under control or she’s ‘left the building’ and it’s up to the farmer.

Scouting intelligence is also used to schedule harvesting as blocks under pressure will be prioritised earlier and planned for the local market.

VICTORY OVER RED SPIDER MITE

JAFF 20, I hope you’re reading this! We’ve found a solution.

Red Spider mites (left) and the damage they inflict (right)

The JAFFs tell us about a challenge they had with red spider mite; tiny little spiders that were sucking the contents of the plant cells out of the avo leaves, turning them bronze, reducing the plants ability to photosynthesize correctly. Being reluctant to spray insecticides, the JAFFs tried a biocontrol agent that had been recommended; no change.

Then a nutrition expert suggested they change the form of nitrogen available to these suckers. He said that, by spraying a foliar nutrient (molybdenum, Zinc, Chelated manganese and Magnesium) the nitrogen in the leaves would be changed, from the free form of ammonia, to nitrates, which the spider mite can’t feed on. The JAFFs tried it and, within a week, the mites had disappeared (with not being able to feed  correctly, they may have starved).

(B&G – please remind me who this advisor was again – I think you said Stephen Schoeman?- Correct)

JAFF 2 then shared another harmless but effective remedy he used, in Mozambique, for a mosquito bug (called Helopeltis) they had up there. It was also feeding on new macadamia flush. It was known as the Tea Mosquito Bug so he contacted the Chairman of the Tea Association to find out how they dealt with it. He explained how they’ve been having great success using silicates. As we know, this nutrient strengthens cell walls making things a little ‘tougher’ for these probiscis-wielding critters. The mac farm tried it and the early results looked promising (and then JAFF moved south). But perhaps this holds some application in discouraging thrips?

The bug causing damage to macadamias and avos in Mozambique.

Back to avos:

Cercospora is probably the single biggest challenge for greenskin avos and the one most farmers spray for. As per the norm, copper spray is also used here. Copper’s ‘harm’ is related to the fact that it’s a fungicide and it kills a range of good fungi along with the ones that ruin the outside skin of a green skin avocado. But there are ways to minimise the impact on the soil and also maximise the efficacy on the skin-based Cercospora; Timing is one – you can follow the Darvas Z model ((Z=-59.33+3.22(Mean weekly temp.) + 0.18(weekly rainfall in mm)), where Z>20 the potential for cercospora infection is high, spraying should be done before this , where Z>5. This isn’t as simple as it sounds and JAFF admits that they defer to spraying once a month from pigeon egg size, until the fruit is off. They use mist blowers and handguns to drench the fruit. Dark-skinned, Hass avos only need 1 or 2 sprays weather dependent, which is not only good news for the soil, it also releases a bit of pressure on the budget as copper prices have increased recently.

Scale and ‘sutu’ mould (brought on by the scale) affects this tree. They won’t spray yet but need to watch it closely.

Phytophthora is, as always, the number one avo issue. This farm injects phosphoric acid across every single tree, once a year, in November (during a root flush) and then sick trees get another dose during the Jan/Feb root flush. When we question the process, JAFF reminds us that “It works and is cost effective.” He adds some guidance in terms of timing; “Some farmers prefer to do it earlier, in September, with that root flush but, with dryland trees, and the possibility of no water, you run the risk of stressing the trees – that’s why we do it when the rains have started.”

POLLINATION

Cross pollination is not a focus. JAFF explains that, because green skins require more copper sprays than black skins, spraying would require more management if orchards were interplanted green and black skins. Here, they prefer to have smaller, pure blocks alongside blocks of a different variety.

Pollination is a focus area though and this is the farm where we found the amazing beehive tyres featured in QUIPS 3. They have hung about 200 of these hives and have brilliant occupancy rates so the farm is literally buzzing! They’ve been so successful in attracting new swarms (sometimes within a week of installation) by making sure the hives are available during swarming season and that they’re primed with the scent of honey. They cost less than R100 to make but need to be hung with a cherry picker to keep them safe from honey badgers and other (2-legged) honey thieves. The Jaffs also have a working relationship with a local bee keeper who provides further hives on the properties .

The Main Bee Tree proudly displaying her 5 hives. JAFF says the 344 macs below this tree are so well set – probably because of the proximity of all these little pollinators. If they were raiding the hives, JAFF estimates that each tyre is carrying about 20kgs of honey.

Despite all the insect life, they still had too many ‘cukes’ last season. “These high numbers were probably related to the wet weather and reduced insect activity over the pollination time,” explains JAFF.

Cukes are unfertilised avos – ‘Cuce’ is short for ‘cucumber’ which is almost what they look like as their ‘belly’ hasn’t swollen with a fertilised seed. They’re really small but the flesh is the same as a normal avo.

Other exciting bee-related info is around the development of toxin-resistant bees. There is an independent beekeeper-cum-scientist on this farm who is building up the resistance of bees to the chemicals used by macadamia farmers …

Chris James is a ‘retired’ beekeeper who was inspired by two factors: 1. The fact that crop pests are becoming resistant to toxins; if they’re insects and bees are insects, then why can’t bees also become resistant … and 2. The fact that ‘bee breeding technology’ is already happening in Europe.

Toxin-tolerant bee project with honey badger-resistant legs.

So, Chris approached our JAFFs who were more than happy to ride the knowledge train to improving our bee populations sustainably and allow Chris to position his hives right next to the chemical mixing site and to support him in developing a super-bee.

Chris has been working on this for 2 years now. The first year was consumed by evaluations but he’s now well into the process of genetic selections.

For those of you who are as fascinated as we are, let’s get a little into the detail …

Chris has a number of hives, all being exposed to pesticides (organophosphates, pyrethroids and imidacloprid). Obviously, under this exposure, some bees will die. The strongest survivors will be further evaluated for hive hygiene (like how well they’re managing varroa mites and small hive beetles – two critters that plague hives and are responsible for wiping out whole swarms). Chris will select eggs from the A+ camps and produce queens from these. A few generations on and the resistant genetics should start saving the bees from the chemicals used on our farms.

Although he’s confident of a positive outcome, Chris faces a number of challenges:

• African Bees are aggressive, known the world over as killer bees for a reason. Working with them is very different from working with European bees who have undergone centuries of genetic alterations to get to the docile state they’re now in.
• Right now, open breeding is slowing the process down. Open breeding is when the queens are released to mate naturally. Obviously this dilutes Chris’ genetics. The alternative is artificial insemination. “OF A BEE?!” we hear you shout (or was that just us?). Yes – bees can be artificially inseminated under a microscope and Chris will be learning this fine art in France as soon as he can.
• Finances – Chris is self-funded and all this research and learning doesn’t come free. Expansion will also require capital, space and good supply of bee food for the roll-out.

The good news is that his current hives are healthy despite some level of toxin (which has been measured and verified by independent laboratories) in both the honey and the wax.

So, what began as a philanthropic journey to save our bees may have Chris on to a commercial solution to our pollination challenges.

HARVESTING

The process is slightly different depending on whether it’s a green or dark skin …

• Green skins: Up in the tree, the picker will cut a longish stem on the fruit, place it in a shoulder bag he’s carrying. When the bag is full, he comes down out the tree, cuts the stem back and places the avo in a crate. “Why cut twice?” was our obvious question and JAFF explains that this is done to avoid any damage to the fruit which often happens when the cutters (usually pole cutters) go too close to the fruit. The poles are 3m long.
• Dark skins: These are broken off at the stem, from the tree. Because this operation handles packing as well, there is no risk of delays wherein bacteria could grow in the ‘navel’ – the fruit is sprayed with a fungicide as soon as it gets into the packhouse. Depending on the season, there is no in-field dipping.

The average picking rate is 30-40 lug boxes per person per day and there are 19kgs in a lug box. Everything goes to the pack house the same day, as it has to be picked and packed within 13 hours.

Inside the pack house which does 3500 tonnes per year.

Here, the fruit is tipped onto the line, smalls are removed and the rest is washed with a dribbled fungicide. From there the avos move on to polishing rollers and driers. They are then graded, sized and packed.

The grading is either Export (4kg cartons), Local (4kg cartons or 10kg jumble cartons) or Reject (20kg bags). The really bad ones are sent to the oil market but that’s less than 1% of the volume.

EXPORT

A definite advantage is having no middleman; dealing directly with the European retailers is highly beneficial. The benefits are felt on the other side of the transaction as well – the retailers really enjoy knowing the actual farmers growing their fresh produce.

SIGNING OUT WITH A CALENDAR SUMMARY

Seen as there were a few schedules, with specific months mentioned, we thought a calendar summary might come in handy …

MONTH	ACTIVITY – Avo Orchards
September	·   Lamb Hass – ready to harvest. ·   Boron, Zinc, Kelp foliar applications on flower (prior to flower opening)
October	·   Rains start end October. ·   Reed is sold into the local market. ·   4 of 6 (15%) fertiliser applications. ·   First copper spray round on green skin avos for cercospora control (fruit at pigeon egg size)
November	·   Reassess the set, based on nutritional supplementation done in August and what the trees are carrying, and adjust the rest of the year’s nutrition programme. ·   Phosphoric acid injections across every single tree (during a root flush). ·   Second copper spray round on green skin avos for cercospora control
December	·   5 of 6 (20%) fertiliser applications. ·   Annual orchard clean up. ·   Third copper copper spray round on green skin avos for cercospora control & first copper spray round on Hass avo’s for pepper spot control
January	·   If Zinc levels in annual test results were low, apply another dose of zinc, together with kelp, on avos’ soft flush. ·   Jan/Feb root flush – Phosphoric acid injections – 2nd dose for sick trees only. ·   Fourth copper spray round on green skin avos for cercospora control & second copper spray round on Hass avo’s for pepper spot control
February	·   Mid Feb to mid-April – Fuerte sold to local market or export, depending. ·   6 of 6 (10%) fertiliser applications. ·   Fifth copper spray round on green skin avos for cercospora control on blocks that will be hung later in the season.
March	·   Soil and leaf analyses done and nutritional programs set up.
April	·   Mid-April to July – Majority Hass sold to international market. ·   1 of 6 (25%) fertiliser applications (start of the new seasons program – flower bud visibility)
May	·   Pruning. ·   Soil ameliorant applications (Lime + Gypsum)
June	·   Pruning. ·  Soil ameliorant applications (Lime + Gypsum)
July	·   Pruning. ·   2 of 6 (10%) fertiliser applications.
August	·   Early in the month – Ryan is ready to harvest. ·   Later in the month – Gwen, Pinkerton & Edranol are ready to harvest. ·   3 of 6 (20%) fertiliser applications. ·   Boron, Zinc, Kelp foliar applications on flower (cauliflower head stage) ·   Visual assessment for nutritional shortages is done and supplementation implemented as required.

And there we go! The avos are off to foreign shores …

And it’s time for us to leave too. This was indeed a proper treat, and the final story so full and rich that two months were required to give it due attention. Thank you again to our two JAFFs who will undoubtedly be leading agriculture into the future. Thank you for making the time to share freely on our humble platform.