A lot of good things are happening. Really good things. We're very proud of the job we've done.
Our blog has been on a brief hiatus because #TeamTomatoJos has been focused on growing and harvesting all of our tomatoes. But we are back and better than ever! Tomato season is coming to a close and we’ve accomplished a lot over the past few months. We’ll have an update on tomato paste processing soon, but we wanted to dedicate this blog post to our farming operations to share our exciting results from the season.
By now, most of our tomatoes are harvested and the team is harvesting the rest as we speak. Overall we had a great season! We did not use seeds that were disease resistant to tomato yellow leaf curl virus (TY), so some of the plants suffered. However, some plots performed very well, particularly in the earlier harvests. One plot even reached yields as high as the equivalent of 50 MT/Ha! We designed different trials on our nucleus farm and were careful to record our process every step of the way, so we learned some valuable information about seed strains and fertilizers as well.
Awaiting Results from the Randomized Block Trial
At the beginning of the season, we did a completely randomized block trial to test what seeds work the best in our area. A randomized block trial is an experimental design that arranges groups into blocks to reduce the variability of certain factors. In our case, we blocked based on the seed type so that we could test which ones produce the highest yield.
Since we are still completing the final harvest we do not have the results of that test – we will have those soon and will report back once we do.
The randomized block trial is the only true experiment that we performed this season, but we also did some observational trials that gave us some helpful feedback…
Bacterial Fertilizer Shows Promise
The first observational trial used bacterial fertilizer as a natural method of helping tomatoes grow. Bacterial fertilizer is developed by isolating local bacteria to see which ones best promote growth for the crops. The bacteria helps by restoring the natural nutrients to the soil without the use of harmful chemicals. We partnered with a company in Abuja called Contec Global that used that approach to create a fertilizer based on our local agricultural profile and tailored to our needs.
We applied our bacterial fertilizer to the leaves, but it can also be applied through the drip irrigation system. Our trial was designed to see the yield difference between three different rates of application of the fertilizer. We divided the hectare into three repetitions – Rep 1, Rep 2, and Rep 3 – that received the same ground preparation, planting regimens, chemical applications, Tomato Jos fertilizer and irrigation regimens. The only difference was the amount of bacterial fertilizer applied to the three repetitions. Rep 1 received no bacterial fertilizer, Rep 2 received half the recommended treatment and Rep 3 received the full recommended treatment. Rep 1 produced the least fruit and Rep 2 produced a bit more, yielding 15% higher than Rep 1. Rep 3 produced even more, yielding 25% better than Rep 1!
These results suggest that the bacterial fertilizer could have positively influenced the yield. However, we need to perform a completely randomized block trial to measure the validity of those observations. In the future, we would also like to try a treatment using the drip irrigation systems using higher concentrations.
Other Fertilizer Observations
Other fertilizers we used included seaweed and Zeba. Our seaweed comes from a company in South Africa – we’re still waiting on those results because we haven’t yet harvested the replication using seaweed.
So what is Zeba? It is basically corn starch that forms a polymer and binds to water. When I asked Art, our VP of Farming, to explain how Zeba works, this is what he told me. “Remember those little rocks you played with as a kid that when you pour water on them, they swell up and turn into gel? It's kind of like that (or maybe I was weird and only played with things like that...). Anyway, as the polymers retain water, the roots will have longer periods of access to the water since it's bound up and not leaching through the soil.” The Zeba seemed to help the plants grow, but we would need to do a randomized block trial to better understand the effect.
Heat and Plant Health
This year the earlier harvests tended to perform better than the later ones. Our farm has had similar results in previous years. We have a couple of theories about why that is happening. Earlier in the season the climate is cooler, so it keeps the pests away for longer. Also, transplanting while it’s cool usually means that more seedlings survive that process because they are not exposed to as much heat stress. So that too, can increase your chance of higher yields.
Cooler weather also plays an important physiological role in the plants’ development. Plants mature faster when they are exposed to higher temperatures, so the fruiting process goes more quickly in the heat. The tomatoes turn out better when the fruiting process goes more slowly, because it gives the plant more time to develop and mature. In case you still don’t understand, here’s another illustration from Art. “If you train for a marathon next week, you won't do as well as if you could train for another month. Plants that are in better environmental conditions (adequate water, nutrients, less heat stress, etc.) will extend their life cycle, and perform better in their own ‘race’, the race of fruiting big red tomatoes.” Unfortunately, there isn’t much we can do about the heat here in Panda. But this is important information to know as we plan for future seasons.