Monday 14th February: Yesterday I received an email from the gallery letting me know that, over the weekend, the top soil of the trees had developed a white mould.
I am not sure what the mould is but the trees, whilst looking a bit shabby with a number of yellowing lower leafs, seemed to growing fairly well. All the same the mould had to be removed and measures to try and stop it happening again put into place. I think the problem was too much water and heat without enough ventilation. This shortage of air and very high humidity may be ideal conditions for the soil mould.
I removed a large portion of the top soil and replaced it with manure taking care not to disturb the roots of the trees. I also removed some of the yellow leaves. Moringa Oleifera trees do not seem to mind any kind of pruning. I sense pruning does improve the condition and welfare of the tree. Removing the lower leaves allows the energy to be used on its new growth. I returned the tress to the propagator and decreased the temperature of the propagator to 20 degrees Celsius (68 degrees Fahrenheit). I then opened all the vents to their widest position. I decided to not water the manure, allowing the soil to dry.
Tuesday 15th February: Checked the trees to see how the changes from yesterday had affected them. I checked for any new signs of mould but couldn’t see any. The trees looked fairly well with some new growth evident on all of them. The humidity was at 54% which is alright although I would like to reduce it a bit more. The temperature did seem a little low so I increased it to 22 degrees Celsius (71.6 degrees Fahrenheit). I have also increased lighting time from 12 hours to 13 hours (6.30 am – 7.30 pm). I will check again tomorrow as I try to get the optimum balance of light, heat and humidity for the trees.
Wednesday 16th February: With exception of one tree that has been struggling for a couple of weeks, the trees are looking fairly well. I decided to water them giving each approximately 8 fluid ounces per tree. I did this to ensure that the nutriments, particularly nitrogen, from the manure were passed to the roots. It is a risk as they have received a lot of water over the last couple of weeks. However I intend to leave the watering for at least 9 days from now to study how the trees are affected and to ensure the soil is dried. I did notice that the leaves give an immediate response to the watering. They tend to form small wrinkles or bubbles on their surface. This eventually smoothes out as the tree relaxes with its environment.
I increased the base temperature to 23 degrees Celsius (73.4 degrees Fahrenheit) and opened all the vents. One problem is that people visiting the installation play with the vents. I am not overly concerned about this as I regularly check the trees and the excellent gallery assistants keep a keen eye on the installation. The humidity was at 46% which where, ideally, I would like it to remain or decrease slightly. I have increased the light hours to 13.5 hours (6 am – 7.30 pm). This is a return to the hours the trees were receiving prior to the re-potting. I am hoping that this arrangement is getting closer to the optimum environment for the trees.
Thursday 17th February: The trees looked unwell this morning with several new yellowing leaves and a general sense of struggling to survive. It is clear to me that the watering yesterday has affected the trees and that the risk I took was a mistake. One of the things that will kill a Moringa Oleifera tree is root rot. This occurs when water does not drain away from the roots hence it being essential to have them in a well drained soil. Growing them in pots makes this even more vital.
The humidity was at 50% slightly over that of yesterday but that isn’t such a concern. What is concerning is that the general temperature in the environment is low. Even with the base temperature set at 23 degrees Celsius (73.4 degrees Fahrenheit) the top soil temperature is approximately 18 degrees Celsius (64.4 degrees Fahrenheit) and can get a low as 16 degrees Celsius (60.8 degrees Fahrenheit). This will not kill the tree but, given that they grow best at temperatures between 25 – 35 degrees Celsius (77 – 95 degrees Fahrenheit), the trees will tend to think its winter and close down their growing cycle. Moringa Oleifera trees can survive low temperatures but not freezing.
At low temperatures the tree will turn their leaves to an almost a white yellow and drop all of them. I saw this happen in my studio whilst conducting experiments to see how the trees would react to a winter climate. This does not mean that the tree is dead as the leaves will regenerate with temperature increase. This how the tree protects itself and saves its energy.
With this in mind I increased the base temperature to 27 degrees Celsius (80.6 degrees Fahrenheit). This gives the top soil temperature of approximately 22 -23 degrees Celsius (71.6 – 73.4 degrees Fahrenheit).
This is at the edge of the minimum temperature range, but a 5 degrees increase is very large and I propose increase it incrementally over the coming weeks if necessary. I noticed that, as the temperature got higher, the humidity went down to 46%. This seemed counterintuitive but is another example of learning through observation. I have also set the vents to half open positions so as to try and hold some heat in the environment whilst keeping humidity down.
This now means that the environment for the Moringa Oleifera trees is in a very different environment from the room it is installed in. The study is at a constant temperature of 19.4 degrees Celsius (66.9 degrees Fahrenheit) at a humidity of between 32% -34% whilst the tree’s environment is at a temperature of 27 degrees Celsius (80.6 degrees Fahrenheit) with a varying humidity between 46% -70%. Further to this, the dawn to dusk hours of the grow lights situates the trees in early to middle spring whilst the study is clearly in middle to late winter; one space with differing sunrises and sunsets; one space with two seasons within it.
Friday 18th February: The struggle continues but this absorbing co –relationship between the Moringa trees and me seems destined to be intense for some time. This morning the trees looked less well than yesterday despite the attempts to increase the temperature in the environment. I checked the temperature and it was at a base level of 21.6 degrees Celsius (70.8 degrees Fahrenheit). This was very low and was not what I set yesterday. I checked the heat monitoring digital display for the propagator and it seemed to have stopped. I reset and rebooted the system. It did seem to immediately start to heat the environment. I can only conclude that their may have been a short power cut during the evening, although this is odd as I would have expected the heat to start up again post the power cut. All in all the trees looked cold and the yellowing on the leaves had increased.
I kept the base temperature at 27 degrees Celsius (80.6 degrees Fahrenheit) but moved the temperature reader to above the soil level. This is to say that the set temperature, 27 degrees Celsius (80.6 degrees Fahrenheit), is set at this level. Consequently the base temperature will increase to achieve this set level as it is positioned higher up the environment casing. The base temperature to achieve the set temperature at this level is 30 Celsius (86 degrees Fahrenheit).
The humidity level was moving between 46 – 49%. I checked the soil and it was still wet. I stayed with the work for a couple of hours monitoring heat and humidity. I also had the opportunity to talk with visitors to the installation. They were really engaged in the work and talking with them did help mitigate the intense concern I have for the trees. At this moment I am unsure if they will survive.
Saturday 19th February: Not much change this morning. There were a few more leaves yellowing but the temperature in the environment has increased. I am relieved to see that the problems with the propagator’s heater had not been repeated. The humidity was at 46%. All in all I sense that the trees are at a crucial point in their growth. Having got the temperature and humidity into some kind of balance I turned my attention to the lights. The grow lights can last for several thousand hours. However they do drop their intensity over time. There is little indication of this in terms of brightness as so it is advisable to keep a log of the hours the lights are on. These lights, along with 4 others, had been used in a prior installation and had been running for approximately 300 hours in this one. The duration hours from the prior installation were approximately 800 hours. Given the total light hours is now approximately 1100 then it advisable to buy two new lights. I plan to buy these tomorrow and install them later in the day.
This been a difficult and intense week where I felt like a bad neighbour in the relationship. The work is in a study and, as such, is conscious of learning and knowledge generated through the closely observed experiences held within the struggle to assist the tree’s growth and the subsequent relationship between trees and me. I also see the work as a bridge or example of priori knowledge that connects with many of the texts held in the study.
It is clear to me that I can follow the authority of mechanistic thinking, with its prescribed set of cause and effect relationships and learn something from the trees. It is also clear that the trees do not necessarily follow the mechanisms we ascribe to them. They are far more complex than that. To learn more and to maintain the relationship I need to fall into ‘slow time’ and become more able to subvert the rationality of mechanistic.
The project is saturated in intricate interactions connecting within and without the complexity of the relationship between the trees and me. As such, negotiating such complexities embodies the realities of uncertainty and trust as essential constituents of these bridges. I know the trees may die. Equally I know that unless I trust the uncertainty of the relationship I will fall back to or run towards a mechanistic thinking that will not serve me or the trees well; I will be burning the bridges or, at best, forgetting to build them.
Approximately 3 cm (1 inch) of growth during this week
The tallest tree is now 53 cm (20.75 inches).