I've been planting lettuce for two years now and I'm doing it organically. Unfortunately, I'm getting inconsistent volume of harvest, maybe because of the quality of chicken manure I'm using as fertilizer.
Anyway, I'm glad I came across the Mittleider method of gardening. I will be slowly converting my garden using the Mittleider method. However, I have some questions. I will be using a grow-box measuring 1.2 meters (4 feet) by 10 meters (32.5 feet) with a planting distance of 20 cm. I'm going to construct 48 grow-beds (I'll be planting 8 grow-boxes with lettuce weekly). I'll be using coconut coir dust (2 parts) and carbonized rice hull (1 part) as my custom-made soil. Is this good?
My other concerns would be how to apply fertilizer when plants will be 3 weeks old. The leaves will be almost touching each other. I'm afraid that during the process of applying
fertilizer, it may come in contact with the leaves. How can I solve this? Also, do I have to cultivate the custom-made soil to incorporate the fertilizer? If I do not cultivate, will it not volatilize?
Another thing. During the preparation of the grow-boxes, is the fertilizer application too much, because pre-plant formula and weekly fertilizer formula are added to the grow-boxes before transplanting. And after transplanting another 21-0-0 fertilizer will be applied, and finally after 3 days the weekly feed formula will again be applied. Isn't it too much? Am I interpreting it correctly?
One last thing (at least for now). Since the width of the grow-box is 1.2 meters and the planting distance is 20 cm, I'll be planting 6 rows of lettuce. If I'm going to automate the watering, is it alright if I use 3 rows of PVC? Can you help me with the design?
That's all for now and thank you very much!
Our writer is obviously experienced in growing leaf lettuce commercially. Please DO NOT think because he is growing 6 rows of lettuce in a 4’-wide box that you can do it successfully in your family garden. Most plants need much more space than that provides.
I’ve used both coconut coir and rice hulls, but I don’t know what “carbonized” means, unless it is that it has been composted with heat. This is not necessary, unless there are bugs, weed seeds, and/or diseases in the material, and only makes it break down much faster, and need to be replaced. I would consider using some concrete sand, especially if the other two are really “dust”. The coarseness and porosity provided by the sand is important for good drainage.
Leaf lettuce will probably not need fertilizing when the transplants are 3 weeks old. Three feedings in addition to the materials placed in the soil before transplanting are all that are necessary. Remember the first feeding is only 3 days after transplanting, and then two more feedings will be sufficient to mature the crop. If plant leaves are touching you must take care not to get fertilizers on the leaves, and if you do, then water thoroughly with a hose immediately, so as not to burn the tender leaves.
Unless you are using urea (46-0-0) in your Weekly Feed mix you do not need to scratch the Weekly Feed into the soil. Urea will volitalize while going through the chemical changes necessary for it to be available to your plants, so that should be placed under the soil surface.
If you are following the instructions you will not be applying too much fertilizer. Mix 2 kg of Pre-Plant and 1 kg of Weekly Feed into the soil of each box before planting, apply ¼ kg of 21-0-0 to each 2 rows of plants immediately after transplanting, and 1/2 kg of Weekly Feed to each two rows of plants weekly thereafter. This represents less than 1/10th of the mineral salts most organic growers apply to the soil AT ONE TIME before planting. Many times manure – and especially chicken manure – will burn emerging and newly transplanted seedlings. What you are doing will NEVER burn your plants if done properly.
To properly water 6 rows of lettuce you will definitely need 3 rows of PVC pipe. Place the pipe in the middle of each set of two rows, and elevated 1/12” to 2” above the soil. This will allow the middle row of holes to dissolve the fertilizers during the course of the week, and the two outside rows of holes will point more directly at the plants’ roots.