Post by wrongway on Jul 20, 2012 21:56:59 GMT -8
In the last few weeks I've been able to determine that my micro climate on the Bolaven Plateau in Laos is actually perfect for potatoes, and all year round, at that. From the beginning I'd decided to grow potatoes in towers made out of recycled automobile tires. However, the topic of growing potatoes in towers is one of those topics where there is just too much information on the internet. And I'd like to put the subject into the context of TPS. I'd appreciate if any of you (Wendy?) could comment on any of the following points I'd like to get clarification on.
1) The variety of potatoes used in this scheme seems to be very important. Most failures I've read about I think are due to variety issues. There are people who tried planting early varieties (Yukon Gold?) in the first tire and kept adding tires and grow media. After months of work they tipped the tower over and were shocked to find that there were potatoes only in the lowermost tire. So a late season variety of potato is needed. I've tentatively chosen three types that I want to play with, and those are October Blue, Skagit Beet Red, and Skagit Valley Gold. Would these varieties be suitable?
2) Late season potatoes are supposed to keep producing until the first frost. The last frost on the Bolaven Plateau was in the 1950's and did some heavy damage to the coffee growers. I think the French had something to do with it as they were just kicked out of Indochina around then and they were the ones who introduced coffee AND potatoes. So, since my temps are from about 65 degrees to 80 degrees year round, how long will late season (indeterminate?) potato plants keep producing potatoes?
3) How do you gauge when to add more grow media? One lady says as soon as the plant begins to show, cover it with another inch of media, then repeat that on, and on, and on. . . That seems like a lot of work. But it does sound like if you let the plant think it's going to be a plant from a given time onwards, that's what it will be, and it won't produce potatoes at higher levels no matter how much media you add. Then there are the people who say that's not true. Then there are the people who say that's true if you use straw or something like that as it's contact with the air that makes the plant decide to stop producing potatoes; if you bury it with denser media it will go back to being a potato producer again. . . Surely there has to be a scientific explanation which can be applied in a practical manner.
Okay, I got more questions, but let's take it in small doses. For anyone who's interested in how I intend to grow the potatoes in wicking beds using tires, read on.
“The wicking bed system is a way of growing plants in which water wicks up from an underground water reservoir. The major advantage is a significant increase in production while water use has been shown to be reduced by up to 50% of conventional practice.†That's from http://http//www.waterright.com.au/wicking_bed_technology.pdf.
In my case, I may be using water full of nutrients from my aquaponic system, and that stuff is a precious commodity to be used sparingly, although there may be enough nutrients in the grow media. Another advantage is I'll probably be able to water once a week and forget about the potatoes. I've read that potatoes like being forgotten about. I should also mention that they will have a greenhouse plastic roof over their heads, though they won't be in a greenhouse.
The first step is shown below. First, dig the reservoir pit. This is about 20cm deep. The reservoir should not be deeper than the capacity for water to wick, which depends on the wicking media, but coir can do about 30cm. Next, line it with leftover greenhouse plastic. Then put down the perforated wicking pipes. These are just fairly large diameter PVC pipes with lots of holes drilled into the sides. They are about 20cm long, too. Then lay the irrigation pipe. This can be perforated or just slotted along the bottom. The inspection/refill bit allows you to check the level of the water in the reservoir. A normal wicking bed would just use boards or something for sides, but I’m going to use old tires because I hope to get them free and worms cannot escape easily (I dare them to try!).
The pit then gets filled in. I’ll probably use river gravel because it is roundish and facilitates a large volume of water. The whole reservoir then gets a layer of shade cloth. This is to keep the grow media in the tires separated from the reservoir. It has to be pushed into the wicking pipes to allow the coir-based media to get down to the bottom of the reservoir. I think this is fairly clever, but I welcome any suggestions. Other wicking beds that I’ve seen just have a corner or two of the reservoir devoid of gravel so the wicking material can be fully immersed in the reservoir’s water.
The tires can now be placed on the wicking bed with the wicking pipes at their centers. As the potato plants grow, more tires are placed on top and grow media added. Potatoes are cool; the right ones will just keep producing potatoes at higher and higher levels, to a certain degree. When the stack reaches about 3 layers and the plant decides that things are going tits up, just kick over the lot and separate the potatoes from the worms and grow media and start again.
1) The variety of potatoes used in this scheme seems to be very important. Most failures I've read about I think are due to variety issues. There are people who tried planting early varieties (Yukon Gold?) in the first tire and kept adding tires and grow media. After months of work they tipped the tower over and were shocked to find that there were potatoes only in the lowermost tire. So a late season variety of potato is needed. I've tentatively chosen three types that I want to play with, and those are October Blue, Skagit Beet Red, and Skagit Valley Gold. Would these varieties be suitable?
2) Late season potatoes are supposed to keep producing until the first frost. The last frost on the Bolaven Plateau was in the 1950's and did some heavy damage to the coffee growers. I think the French had something to do with it as they were just kicked out of Indochina around then and they were the ones who introduced coffee AND potatoes. So, since my temps are from about 65 degrees to 80 degrees year round, how long will late season (indeterminate?) potato plants keep producing potatoes?
3) How do you gauge when to add more grow media? One lady says as soon as the plant begins to show, cover it with another inch of media, then repeat that on, and on, and on. . . That seems like a lot of work. But it does sound like if you let the plant think it's going to be a plant from a given time onwards, that's what it will be, and it won't produce potatoes at higher levels no matter how much media you add. Then there are the people who say that's not true. Then there are the people who say that's true if you use straw or something like that as it's contact with the air that makes the plant decide to stop producing potatoes; if you bury it with denser media it will go back to being a potato producer again. . . Surely there has to be a scientific explanation which can be applied in a practical manner.
Okay, I got more questions, but let's take it in small doses. For anyone who's interested in how I intend to grow the potatoes in wicking beds using tires, read on.
“The wicking bed system is a way of growing plants in which water wicks up from an underground water reservoir. The major advantage is a significant increase in production while water use has been shown to be reduced by up to 50% of conventional practice.†That's from http://http//www.waterright.com.au/wicking_bed_technology.pdf.
In my case, I may be using water full of nutrients from my aquaponic system, and that stuff is a precious commodity to be used sparingly, although there may be enough nutrients in the grow media. Another advantage is I'll probably be able to water once a week and forget about the potatoes. I've read that potatoes like being forgotten about. I should also mention that they will have a greenhouse plastic roof over their heads, though they won't be in a greenhouse.
The first step is shown below. First, dig the reservoir pit. This is about 20cm deep. The reservoir should not be deeper than the capacity for water to wick, which depends on the wicking media, but coir can do about 30cm. Next, line it with leftover greenhouse plastic. Then put down the perforated wicking pipes. These are just fairly large diameter PVC pipes with lots of holes drilled into the sides. They are about 20cm long, too. Then lay the irrigation pipe. This can be perforated or just slotted along the bottom. The inspection/refill bit allows you to check the level of the water in the reservoir. A normal wicking bed would just use boards or something for sides, but I’m going to use old tires because I hope to get them free and worms cannot escape easily (I dare them to try!).
The pit then gets filled in. I’ll probably use river gravel because it is roundish and facilitates a large volume of water. The whole reservoir then gets a layer of shade cloth. This is to keep the grow media in the tires separated from the reservoir. It has to be pushed into the wicking pipes to allow the coir-based media to get down to the bottom of the reservoir. I think this is fairly clever, but I welcome any suggestions. Other wicking beds that I’ve seen just have a corner or two of the reservoir devoid of gravel so the wicking material can be fully immersed in the reservoir’s water.
The tires can now be placed on the wicking bed with the wicking pipes at their centers. As the potato plants grow, more tires are placed on top and grow media added. Potatoes are cool; the right ones will just keep producing potatoes at higher and higher levels, to a certain degree. When the stack reaches about 3 layers and the plant decides that things are going tits up, just kick over the lot and separate the potatoes from the worms and grow media and start again.
I love to see more people interested in food security and I believe potato being so adaptable could provide as TPS one good food source.