
We grow our seedlings in compartmentalized expanded polystyrene trays. The cells are filled with a growing medium, in this case coir pith, and a seed is placed in each cell and grown out to maturity. This can take as little as four weeks in summer for tomato seed or up to four months in the case of gum tree seedlings as seen above. A seedling is deemed mature when it can be pulled from the cell and the roots hold the medium in a plug which will remain intact until it can be planted into the field. It also needs to be tall enough to be planted easily and not so tall that the leaf area will tax the roots ability to take up enough water in what, for the plant, is a stressful transition. There are other criteria that need to be met such as hardness of the leaves but that’s getting boring.
Being made of polystyrene the trays are light and rigid, which makes them easy to handle. It also makes it easy for the plant to grow its roots into the polystyrene which makes the seedling difficult to pull out of the tray. New trays have a smooth surface which is difficult for the roots to penetrate but as the trays age their surface becomes pitted and the plants’ roots can penetrate the polystyrene. To reduce this effect we dip the trays in a solution of copper oxychloride and water soluble glue. This creates a localized toxicity in the tips of the roots which stops them growing into the polystyrene and serves to sterilize the tray. Mostly it’s effective but as the tray ages and the surface becomes rough the roots grow into it anyway. The buildup of copper over many uses of the tray also causes a more general toxicity in the plant which can manifest itself as leaf discolouration and poor growth.
This general toxicity is most evident in gum seedlings as discoloured leaves and poor tip growth though in other seedlings it manifests as a general lack of vigour. I have noticed this for some years and when new trays are bought there was a noticeable “new tray effect” which I couldn’t really nail down to anything specific.
The coir pith we use is a by-product of the coir industry in India and other Asian countries. It’s the cork material that’s left over when the fiber has been extracted for ropes and mats. It has no nutrients in it so all must be added in the form of various chemical fertilizers. Organic we are not. This means that there’s little space for error and small changes in the formula can have major effects. Fortunately most of the work in this type of horticulture has been done long ago, albeit on other media, so it’s not as hit-and-miss as it may sound. Unfortunately I have a tendency to fiddle to try and get just that little bit of extra performance out of the system.
So when the gum seedlings started to become discoloured some years ago I put it down to something I’d done to the fertilizer formula. Thinking that it was a phosphate toxicity I designed a simple experiment. I bought several new trays, made sure they weren’t dipped in copper, then mixed differing quantities of single superphosphate that we normally use into the coir pith and grew out the gum seedlings. They were all good seedlings including those that should have had toxicity symptoms and those that had no single superphosphate added at all. It was that “new tray effect” and I knew it had to be the copper dip.
In Zimbabwe trash recycling is not a vibrant industry. There is a large municipal dump that I drive past on the way to work with a large warehouse building on it with “RECYCLING PLANT” painted on the front. Whether any recycling actually happens there is unknown. It’s part owned by one of the President’s sons but that’s a topic for another blog post. The old polystyrene trays we use end up on this dump site and add to the general pollution. It bothers me but the alternative is to import plastic trays from South Africa and they are very expensive and would likely not be recycled either. So I buy more of the local trays when I have to.
The gum seedling in the above photo is a good one. Though still young it has good root development, good leaf colour and good growth. It’s a product of a new tray – part of a batch that I bought earlier this year to replace older trays that were causing the copper toxicity symptoms. I have been seeing a general malaise in the tomato seedlings we are growing in old trays and should really replace them too. But there’s a problem.
I lease part of a property that supports my landlady’s ornamental nursery, another tenant’s rose nursery and the landlady’s son’s container rental business. The remainder of the property, some 10ha, is not utilized largely because we are in a bad area for sub-surface water and the three boreholes would not support irrigated cropping of any sort.
The 400ha of land on the boundary of “our” land is owned by a politically connected person whom I will call G. She acquired the land some time ago and set about building a wall around it. This is not just any wall – 3m high it has, a reinforced concrete core, a course of bricks on either side, pillars every 4m and topped with cornicing. It’s 9km long (measured on Google Earth) and is estimated to have cost US$500 – US$600 per metre. At a minimum $45 million G has clout and access to capital. So it was not without concern that we waited to see if the wall would include “our” property. It stopped either side.
My landlady’s son decided that the best way to make the property less attractive to acquisition by G and her ilk would be to develop it. Half the property was duly sold to a development company for construction of high density housing on condition that they changed the title deed to “development” rather than “agricultural” which is less attractive to the likes of G.
This development means that I will lose about a third of my current capacity and access to two boreholes that provide the bulk of my water. Remaining viable in a business that relies on large turnover on low value items/seedlings is going to be a challenge. So do I invest in new trays?
I was initially told that I would have about two years use out of the current two boreholes and that was six months ago. My landlady has had another two drilled on the remaining property but they are not very prolific. Uncertain times but to throw in the towel now on the premise that my business will fail would be defeatist. Tomorrow I will place an order for 2,000 new trays.








Mick Jagger, a frog and AI
27 10 2025Memory’s a funny thing. I woke up one morning recently and told Marianne I’d just remembered the punch line of an old joke; “It’s a knick knack Patty Wack, give the frog a loan”. She smiled and said “But there’s more to it than that” and added “he’s old man is a Rolling Stone”. Of course I had to see if I could find the original on the internet and called up the faithful Google search engine which Google assures me heavily uses AI.
Just entering “Patty Wack” came up with one suggested search for the correct joke even correcting for my alternative spelling of “Wack”. Quite impressive, there aren’t too many patty wacks out there.
Not bad for a start but on reading the original joke I discovered that a knick knack is a critical part. So I thought I’d include it in the search. Just by itself and Google didn’t come up with any alternative searches that would have led me to the joke.
Searching on “knick knack patty” was surprisingly successful with an accurate search term as the third item. Not too many other suggestions though it seemed to suggest that I might have meant Paddy not Patty.
The most successful search term was “knick knack patty wack frog” which brought the joke up to the top of the list for suggested searches but I thought that I was giving rather a lot of information out to start with so decided to up the task difficulty a bit.
The punch line of the joke, you can look up the whole thing here, is: “It’s a knick knack Patty Whack give the frog a loan, his old man is a Rolling Stone” where the Rolling Stone is referencing Mick Jagger. I decided to see if the AI would associate Mick Jagger with a frog joke and entered “Mick Jagger frog loan joke”. Nope, not a single other search was suggested – clearly I was being very specific. Curiously “Mick Jagger frog” did suggest another more specific search as the first item. Can’t think why Angie got in there. Yes, I can remember the song! We all used to crowd into a prep room in the school hostel on Saturday night and watch Top of the Pops on a black and white television. Mick doing his best emotional bit in a big floppy hat. “Angie. A-aaaaaangie. Can’t say we never tried”.
Perhaps a case of less is more?
There are of course many variants of AI to be found all over the internet. Perhaps one of the best known is ChatGPT. I have used it a bit when stuck on my programming projects and it’s been useful in suggesting solutions. I did get to use it today on another project and was really impressed.
My business is in trouble. Two weeks ago I was within a few days of running my bank account dry. It was time to see where the problem was. It didn’t take a lot of doing. I am selling my seedlings for less than they cost me to produce. My bookkeeper commented that my salaries and wages were too high a proportion of my overall costs but there is little that I can do about it now – nobody is going to accept a wage cut. I wondered if I could put the business into administration (yes, I Googled what that entails) and be closed down. I didn’t see how I could sell a business that is not a going concern.
There are at least five other commercial nurseries in Harare that I know of. My foreman on occasion phones them to see what they are charging. The biggest is charging substantially less than I am and I have no idea how they do it. I also know what they are growing as we use the same seed supplier and I am friendly with one of the staff there. It’s mainly tomatoes and lots of them. This makes me think they are supplying the farmers who grow for a well-known fast food company. It was time to see if I could get in on the action.
Zimbabwe being what it is, it was not difficult to find out who the procurement officer of the above-mentioned fast food chain is. Marianne, being more adept at marketing than me (not difficult – there are disadvantages of a science degree), helped me put together the approach email. The reply was non-committal. A different approach was needed but at least we had not been rebuffed.
Given our lack of marketing skills we decided to ask Maria. She’s a formidable communicator and the driving force behind HIFA (Harare International Festival of the Arts) that ran for several years and was the arts and entertainment highlight of the year. She agreed to draft something.
While I was mulling over what Maria had put together Marianne was chatting to her sister in Cape Town who has a tour company for older women . Mandy suggested we get ChatGPT to draft something as she uses it quite a lot and was impressed. She did mention that it was a good idea to be polite when asking it for assistance! So I logged in and made my request. The response is too long to reproduce here but I was very impressed. It was just what I was looking for with all the right marketing language. So tomorrow I will send off another email to see if I can get access to the produce suppliers. Nothing ventured. There will be a few adjustments to the original text – “Warm regards” will be replaced with “Regards” which I consider a bit less familiar.
I can of course remember back in the 1980s when AI stood for artificial insemination. One of my housemates at university was doing an animal science degree and they had been harvesting semen from a bull. He wondered aloud if an orgasm for a bull was as much fun as it was for a human. Someone else chipped in that it was physiologically identical, the difference being that the bull could not remember what was so pleasant.
Looking up artificial insemination on the internet (yes Google AI) I saw that it is widely practiced for women who cannot get pregnant the natural way. While there doesn’t appear to be human AI on offer in Zimbabwe (but plenty of livestock options) there are a couple of sites advertising IVF (in vitro fertilization). Most of us older folk can remember that Louise Brown was the first example of this “test tube baby” process. As one fellow student commented all those years ago: “The worst thing about being a test-tube baby is you know for sure that your old man’s a wanker”. If you don’t know what that means try a Google AI search!
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Tags: AI, artificial-intelligence, ChatGPT, fiction, HIFA, IVF, Kermit the frog, knick knack, Mick Jagger, Patty Wack, Technology, The Adventurous Ewe, writing
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