Fertilizing lemon trees follows the typical protocol growers use to keep citrus trees healthy and strong. Citrus trees are heavy feeders, so it is best to fertilize them every 4-6 weeks during their active growing season (spring and summer) and every 1-3 months during the dormant period (fall and winter). Lemon trees need a fertilizer containing a good quality source of nitrogen.
The nutrient ratio of fertilizers used to feed lemon trees should not be higher than 8-8-8 for optimum growth. These numbers found on a fertilizer label are the N-P-K ratio; the consumer can look at this ratio and determine the percentage, by weight, of the nitrogen (N), phosphorus (P), and potassium (K) in the fertilizer.
For instance, in an 8-8-8 formula, a 10-pound bag of fertilizer would contain the following: 0.8 pounds of nitrogen, 0.8 pounds of phosphorus, and 0.8 pounds of potassium.
All plants have essential nutrients needed for growth. Nitrogen is one of the main essential nutrients; its main responsibility in a plant is vegetative growth.
It is used in the plant to construct amino acids which are the building blocks for protein; nitrogen is a major component of chlorophyll and helps to make the foliage green, and it is also necessary for the plant’s enzymatic reactions.
Phosphorus is a component in DNA and RNA (the genetic building blocks within plant cells) and is needed for root growth and flowering.
Potassium works more indirectly than the other two nutrients. It is not a component of any plant parts but activates many of the enzymatic reactions that occur within the plant, making it imperative for overall plant health.
Recommended Organic Fertilizers For Lemon Tree
#1. BGI Fertilizers CitrusGain.
BGI Fertilizers CitrusGain is an 8-3-9 nutrient ratio fertilizer, is specially formulated for citrus and trees, meeting the specific requirements of these plants.
Citrus trees/plants need adequate amounts of essential nutrients to develop strong root systems, maintain overall tree health, and produce high-yielding, high-quality fruit.
CitrusGain contains nitrogen, potassium, magnesium, manganese, iron, copper, zinc, sulfur, other macronutrients and micronutrients to meet these needs.
Application Note: Apply every 4-6 weeks during the growing season. Sprinkle evenly, in a circular pattern, under the tree/plant outward to the drip line; do not apply directly against the trunk or base of the plant.
#2. Jobe’s Organics Fruit & Citrus Fertilizer with Biozome
This fertilizer is an OMRI certified organic, granular fertilizer. In other words, it is safe for the environment and because it is granular it is a slow-release fertilizer meaning your trees will be receiving food over a longer period.
Also, it is specially formulated to provide fruit-bearing plants the nutrients they need to yield abundant, healthy citrus fruit.
Jobe’s Organics Fruit & Citrus Fertilizer contains Biozome, bone meal, feather meal, potash and manure with an N-P-K ratio of 3-5-5. Biozome is a proprietary product containing a combination of healthy bacteria, mycorrhizal fungi, and microorganisms that helps to improve soil texture, and also increase water infiltration and retention.
Application Note: Apply every 2-3 months for optimum results.
#3. Espoma Citrus-tone 5-2-6 Plant Food
Espoma Citrus-tone 5-2-6 Plant Food is An all natural, organic plant food based on leading university recommendations and formulated for citrus, fruit, and nut trees.
Espoma Citrus-tone contains a 5-2-6 ratio of nitrogen/phosphorus/potassium and is enhanced with thousands of living soil microbes to aid in the development of the entire tree, as well as enhancing the soil ecosystem.
It is a slow-release formulation, providing small, continuous amounts of nutrients to the lemon tree over a sustained length of time.
Application Note: Apply at the recommended rates (2-8 pounds depending on the size of the tree) three times a year for optimum results: late winter as a pre-bloom application to enhance flowering, late spring as a post-bloom application to enhance fruit set, and then again in the fall to replace nutrients already used by the tree.
#4. Dr. Earth Blood Meal
Organic gardeners have used blood meal as a natural fertilizer for a long time.
It is one of the most utilized single-nutrient fertilizers in home gardens. Bloodmeal is known for containing a quickly soluble form of all essential plant nutrients: nitrogen, phosphorus, potassium, magnesium, and many others.
Dr. Earth Blood Meal is an excellent source of organic nitrogen for lemon trees promoting dark, green foliage and excellent plant growth. It also contains five strains of beneficial soil microbes.
Use it to fertilize heavily in the spring and summer; fertilize more lightly in the fall and winter when the lemon tree isn’t growing as actively.
Application Note: Application rates depend on the nutrient ratio of the specific product purchased. Dr. Earth Blood Meal contains an N-P-K ratio of 13-0-0. For lemon trees, work one cup of Dr. Earth Blood Meal into the soil, within the drip line, for every inch of trunk diameter.
#5. Down to Earth Fish Meal Fertilizer
Fish Meal is an excellent source of both nitrogen and phosphorus.
It is suitable for use on all types of plants and trees it enhances microbial activity in the soil, it promotes vigorous root development, and provides an early-season boost of nitrogen for plants/trees.
Down to Earth Fish Meal Fertilizer is carefully blended from natural, high quality, organic sources so the nutrients are in the ideal proportions for plant use.
A high-quality formula means this fertilizer never contains low-quality filler ingredients or synthetic fertilizers.
Application Note: For optimum results apply 1-2 pounds of fertilizer per 1” of trunk diameter, sprinkling from the base of the lemon tree outward to the drip line. Mix well into the soil and water thoroughly.