I purchased a potted patio lemon tree 8 months ago from Wal-mart. The plant looks healthy, a fruit started 3 months ago,. it is now 2x the size of a regular lemon --and all green since it started !! WHY___HELP !!!
Lemons Are Green ??!!
Certified GKH Gardening Expert
This is quite normal. This can take up to 9 months to turn yellow. The size is a very good sign. This indicates that the plant is well cared for. There is no cause for concern. Think of it as a growing baby, and care for it to the best of your ability.
I can tell you from experience, that container citrus are needy in terms of care. You will want to keep dolomitic lime and iron sulfate on hand at all times. This will prevent many problems that you will, inevitably, face while growing this tree. Use these at least once per year, or twice for good measure. You will also want to fertilize with a citrus fertilizer once per year for good measure, and fruit production. Keep the tree from freezing, or cold temperatures while the fruit is forming, and you will be rewarded with a wonderful crop.
Here is an article for further reading: https://www.gardeningknowhow.com/edible/fruits/lemons/growing-lemon-trees-containers.htm