I am planning on growing a dwarf lemon tree indoors in North Carolina, but I am not sure which type of soil or fertilizer would be best. I do not know much about lemon trees so any advice would be greatly appreciated. Thanks.
For container trees the best fertilizer (easiest to use) is a slow release fertilizer with trace minerals. Osmocote and Dynamite have a product you can find at most garden centers. You want the one that is closest to the 5-1-3 NPK ratio that citrus use (like 19-6-12 not the ones that are like 8-8-8). With slow release pellets you fertilize according to container size about every 3-4 months. As for soil, or more accurately, potting media, there are recipies on this forum for CHC based media, but I use a mix of 4 parts pine bark chunks to 1 part peat moss (or peat moss based potting media). All potting media will breakdown over time and needs to be replaced, the pine bark media last about 1 yr the CHC will last several.
I used CHC and peat in the past, Which works GREAT for container grown citrus The problem I've found in using this mix is that the peat likes to settle at the bottom over time which can cause problems in the future for drainage. At this time I am using a CHC and coir mix for testing. The last order of CHC that I ordered containes what I feel is a good supply of coir which is found on at the bottom of the washings or cleaning the CHC. Myself I don't like the 10% water flow rate for watering, It should be fast flowing yet retain water, I also do not believe in the 5-1-3 NPK ratio to be correct. Perhaps in the perfect world this finding may be correct, We do not have common fert like 30-10-10 for growing citrus. It all depends on the waters Ph values and soil testing for the 5-1-3 to work correctly. Perhaps this understanding on the 5-1-3 could be further explaned. I'm willing to learn.
I absolutely agree with Skeeterbug, about using a fertilizer that has a ratio as close as possible to 5-1-3 when fertilizing containerized citrus. When a healthy citrus tree absorbs nutrients from the soil, the root system will always absorb 5 parts nitrogen for every 1 part phosphorus, and 3 parts potassium. There are many commercial fertilizers products. They must be chosen according to the proper replacing of minerals that were used, and their ratio. Fertilization must respect this ratio when the mineral content in the leaves is satisfactory. This exact fertilizer ratio is sometimes hard to find, so look for and purchase the closest ratio you can locate. Citrus trees can be grown "OK" with other fertilizer formulations, but there will always be a crop difference when the ratio is out of balance. Additionally, other formulations, especially ones with higher ratios, can result in a toxic soluble salt build up in the root system. High nitrogen fertilizers, especially causes a reduction in the citrus crop. The most common growth medium that is used by the nursery industry world wide is 4 parts ground conifer (pine) bark, one part sphagnum peat moss, and one part COARSE sand (not play sand). For citrus trees I use 4 parts Coconut Husk Chips (CHC) and 1 part peat moss. The formula that Skeeertbug gave (4 parts pine and 1 part peat moss), would work the same as the formula that I use, but just would not last as long. Coir can be exchanged for peat moss if you wish. - The best of luck to you and to your lemon. Take care. - Millet
Bob, It's not Skeeter that I pointed to . Sorry Skeet. Its Millets findings that promotes the 5-1-3 findings for this ferts. Why don't we have a common fert. like the 5-1-3 that YOU push. I guess soil testing an Ph values means nothing. Millet post you findings for 5-1-3 findings.
The 5-1-3 ratio is not as important for inground citrus where the fertilizer can be bound by minerals, degraded by bacteria or leaches down into the soil at various rates. However, excess P can permanently bind some minerals and reduce their availability. Soil test can be very useful for inground trees, but are not often used on container media. Soluble salt buildup is not often a problem in soil like it is for containers. I use a balanced fertilizer like 8-8-8 plus N in the form of ammonium sulfate for my inground trees, but I use the Osmocote for my container citrus. One of the reasons I use pine bark is that I get a lot of it free -- I pick up big slabs of it from dead trees when I am in the woods --and it works.
Skeeter is correct that soil testing is very rarely done on containerized trees. I don't know why anyone would even want to do a soil test on a container tree. Even if a test was done, I seriously doubt that very many hobby citrus growers would be capable of understanding the soil test report if they read it anyway. - Millet
Skeet, Millet, Thanks for taking the time for your postings, I now understand the reasoning behind the 5-1-3 ratio. I felt this applied for all citrus, inground and containers. Thank You both for your time in helping me understand.
