Geraniums are prized for their vibrant, continuous blooms throughout the growing season. Maintaining robust flowering requires a consistent supply of nutrients. While commercial fertilizers are available, many gardeners prefer accessible, low-cost alternatives using common household materials. Homemade solutions allow for greater control over ingredients and support healthy foliage and prolific flower development.
Understanding Geranium Nutrient Requirements
Geraniums require a balanced diet, but the ratio of nutrients is important for encouraging flowers over excessive green growth. Nitrogen (N) primarily supports vegetative growth, meaning high amounts will lead to lush leaves at the expense of blooms. For this reason, the fertilizer provided should moderate nitrogen levels to promote compact, sturdy growth.
Phosphorus (P) and potassium (K) drive flower production. Phosphorus is necessary for energy transfer and robust root development, supporting the plant’s structure and ability to flower. Potassium aids in water regulation, disease resistance, and is involved in producing high-quality blooms.
Geraniums generally prefer a soil environment that is slightly acidic to neutral, ideally maintaining a pH level between 5.8 and 6.5. This range ensures that essential micronutrients, like iron and manganese, remain available for the plant to absorb. When the pH shifts too far outside this zone, nutrients can become “locked up” in the soil, preventing the plant from accessing them even if they are present.
Simple Homemade Fertilizer Recipes
One of the simplest liquid boosters is a solution made with Epsom salt, which delivers two secondary nutrients: magnesium and sulfur. To prepare this mixture, dissolve one tablespoon of Epsom salt in one gallon of water. Magnesium aids in photosynthesis and the absorption of phosphorus, while sulfur helps with the formation of chlorophyll.
The liquid solution is ready for immediate use once the crystals are fully dissolved. It provides a quick nutrient boost that deepens the green color of leaves and assists in flower bud formation. Applying this occasionally supplements the primary feeding regimen without over-fertilizing the plant.
A mixture of kitchen scraps provides a range of primary and secondary nutrients. Gather used coffee grounds, dried banana peels, and crushed eggshells. Coffee grounds supply nitrogen, phosphorus, and potassium, but must be completely dried out first to prevent mold growth.
Eggshells are an excellent, slow-release source of calcium, important for strong cell walls and overall plant structure. Dried banana peels are rich in potassium, which directly supports flowering. To create the finished dry fertilizer, crush the eggshells into a fine powder and mix them with the dry coffee grounds and finely chopped banana peels.
Proper Application and Feeding Schedule
During the active growing season, which typically runs from spring through early fall, geraniums benefit from feeding every two to four weeks. Consistent feeding is especially important for container-grown plants, as nutrients leach out of the soil more quickly with frequent watering.
When applying any liquid feed, such as the Epsom salt solution, ensure the soil is already moist before watering with the fertilizer solution. Applying fertilizer to dry soil can cause root burn due to a high concentration of salts. Pour the solution evenly around the base of the plant until it begins to drain from the bottom of the pot, ensuring the roots absorb the nutrients.
For the dry kitchen scrap mixture, lightly sprinkle a small amount around the base of the plant, being careful not to pile it directly against the stem. Gently scratch the mixture into the top inch of the soil using a small trowel or fork. This action helps incorporate the organic matter and nutrients into the root zone where they can be slowly broken down.
Avoid over-fertilization, as this can lead to a buildup of mineral salts in the soil, which can damage the roots. If a white crust begins to form on the soil surface, flush the container with plain water until it runs freely from the drainage holes to wash away excess salts. Stop all feeding during the late fall and winter months when the geranium naturally enters a period of dormancy.