How to Choose the Perfect Hydrangea Fertilizer
Hydrangeas are beloved for their large, showy flower heads and vibrant colors. To keep your hydrangeas healthy and blooming their best, it’s important to choose the right fertilizer. Here’s a comprehensive guide to help you select the best fertilizer for your specific hydrangea needs.
Know Your Hydrangea Type
Different types of hydrangeas have different fertilizer requirements. The most common types include:
- Bigleaf hydrangeas: These hydrangeas have large, round flower heads that can change color depending on the soil pH.
- Mountain hydrangeas: Similar to bigleaf hydrangeas, mountain hydrangeas also have color-changing flowers.
- Oakleaf hydrangeas: These hydrangeas have unique oak-shaped leaves and produce white to purplish-pink flowers.
- Panicle hydrangeas: Panicle hydrangeas produce cone-shaped flower heads in late summer.
- Smooth hydrangeas: These hydrangeas have smaller, ball-shaped flower heads that are typically white or pink.
Organic vs. Inorganic Fertilizers
Organic fertilizers are made from natural ingredients, such as compost, manure, and bone meal. Inorganic fertilizers are synthetic and contain chemical nutrients. Both types of fertilizers can provide essential nutrients for hydrangeas, but they have different advantages and disadvantages.
- Organic fertilizers: Eco-friendly, improve soil health, may not be as potent as inorganic fertilizers.
- Inorganic fertilizers: Cheaper, produce larger blooms, can increase soil acidity.
Choosing an Inorganic Fertilizer
For inorganic fertilizers, look for a balanced formula with equal amounts of nitrogen (N), phosphorus (P), and potassium (K). A ratio of 10-10-10 N-P-K is a good choice for hydrangeas. Fertilizers with a higher phosphorus content will promote larger and more abundant blooms.
Types of Fertilizer Forms
Hydrangea fertilizers come in three main forms:
- Liquid fertilizers: Fast-acting, can be applied directly to the leaves or soil.
- Granules: Can be slow- or fast-release, provide nutrients over a longer period.
- Spikes: Timed-release, provide nutrients gradually over several months.
How and When to Fertilize
Hydrangeas benefit from fertilizer applied in mid- to late spring, and at additional intervals throughout the growing season.
- Slow-release fertilizers: Apply once or twice a year and cover lightly with soil.
- Timed-release fertilizers: Apply a few times a year in spring and fall.
- Fast-release fertilizers: Apply every one to two weeks during the growing season.
Stop fertilizing after August to avoid encouraging late growth that could be damaged by frost. In late winter, feed hydrangeas with an all-purpose fertilizer to give them a headstart for the new growing season.
Changing the Color of Hydrangea Flowers
The color of bigleaf and mountain hydrangeas can be changed by adjusting the soil pH. To turn flowers blue, add sulfur to the soil. To turn flowers pink, add lime.
Additional Tips
- Hydrangeas prefer slightly acidic soil with a pH of 5.5 to 6.5.
- Avoid over-fertilizing, as this can damage the plant.
- Water hydrangeas deeply and regularly, especially during hot, dry weather.
- Mulch around hydrangeas to help retain moisture and suppress weeds.
By following these tips, you can choose the best fertilizer for your hydrangeas and help them thrive and produce beautiful blooms season after season.