Order lemon tree fertilizer here. Fertilizing is an important aspect of growing lemon trees. Lemons will flower and fruit almost continuously if they are fed following these instructions.
You can feed a lemon tree with any plant food you happen to have on hand and it won't hurt it. But as citrus requires certain specific trace nutrients, a food labeled as a citrus food makes the best lemon tree fertilizer.
Brand does not matter.
Organic or synthetic is a matter of your personal choice.
I've used both for lemon tree care over the years and I've never noticed a difference in the growth of the trees or the quality of the fruit using one vs the other.
Whether you use a liquid or granular food is, likewise, a matter of personal preference. They work about the same.
Fertilize your lemon trees in late spring, mid summer, and early fall. Use a little super phosphate, in addition to the more complete fertilizer, in the spring if you want heavy flowering and continuous fruit production throughout the growing season.
Just sprinkle the powder (about a 1/4 cup for each foot of the tree's height) under the tree at the drip line.
Use the same citrus food you would give an outdoor tree but apply it more frequently. The feeding schedule above will keep a containerized tree healthy.
But to maximize fruit production, feed the tree every 4-6 weeks.
Follow the instructions on the label of the citrus food you are using as to the amount to apply. When in doubt, apply less. Never use more as too much fertilizer at once may burn the tree's leaves.
Citrus fertilizer spikes make feeding your trees neat and easy. You can use the outdoor spikes on lemon trees growing in pots. Just break them in half. Use 1 spike per pot.
Lemon Growing Info: