10 Best Houseplant Fertilizers 2026 in the United States

FoxFarm Big Bloom is a liquid fertilizer designed mainly for flowering and fruiting plants, making it a good fit if you want to boost blooms and improve flavor in herbs, fruits, and vegetables. Its NPK ratio is very low in nitrogen (0) and phosphorus (0.5) and potassium (0.7), which means it's not meant for heavy leaf growth but focuses more on flower and fruit development.

This product is organic, using natural ingredients like earthworm castings and bat guano, so it's a gentle option for indoor and outdoor plants without harmful chemicals. It also includes micronutrients that support root strength and overall plant health. One of its strengths is the ease of use as a liquid concentrate that mixes with water, making feeding your plants straightforward. However, if you need a fertilizer that promotes leafy growth or has a balanced NPK ratio for general feeding, this might not be ideal. It’s also best suited for plants that bloom or produce fruit, so for general houseplants or foliage plants, you might want a different formula.

Big Bloom is a versatile, organic fertilizer suitable for gardeners focused on flower and fruit production who want a natural feeding option that strengthens roots and enhances flavor.

Miracle-Gro Water Soluble All Purpose Plant Food is designed to nourish a wide range of plants, from indoor houseplants to outdoor vegetables, flowers, trees, and shrubs. Its NPK ratio of 24-8-16 means it has a strong nitrogen content, which supports leafy growth, moderate phosphorus for root and flower development, and good potassium for overall plant health. This makes it effective for general use, especially if you want your plants to grow bigger and greener quickly. The product is synthetic and comes in granule form that dissolves in water, making it easy to apply with a watering can or garden feeder. It covers a large area, about 2,000 square feet per 5-pound bag, which is convenient for gardeners with many plants.

While it feeds all types of plants, it doesn’t have specialized formulas tailored to specific plants, so it may not meet unique nutrient needs that some sensitive plants require. Also, it doesn’t list added micronutrients like iron or magnesium, which can sometimes be important for certain houseplants. Application instructions are clear and flexible for indoor and outdoor use, but frequent feeding might be needed to maintain results because it works quickly but doesn't provide slow-release nutrition.

If you want an easy-to-use, versatile, and fast-acting fertilizer for most plants, this is a solid choice. However, if you prefer organic options or fertilizers tailored to particular houseplants, other products might be more suitable.

The FoxFarm Fertilizer Soil Trio is a set of three organic liquid fertilizers designed to support plants throughout their growing cycle. It includes Grow Big to encourage lush green growth, Tiger Bloom to boost flowering with phosphorus, and Big Bloom to strengthen roots and improve nutrient uptake. This combination covers the main stages of plant development, making it suitable for a variety of flowering and fruiting plants. Being organic, it’s a good choice if you prefer natural products over synthetic fertilizers.

The trio offers a balanced approach with different formulas for specific growth phases, simplifying feeding with the included chart. Application is easy by mixing with water or spraying, and you can adjust the frequency based on your plant’s needs. It requires some attention to timing since each bottle targets a particular growth stage rather than all-in-one use.

This fertilizer set is ideal for gardeners who want to feed houseplants or garden vegetables and flowers with quality organic nutrients and are comfortable managing multiple products throughout the season.