Learning how to fertilize hydrangea shrubs is equally as important as the type of fertilizer chosen. Apply a slow-release chemical for shrubs and trees once a year. Depending on the variety, a balanced time-release fertilizer can be applied a few times a year, in spring and early fall.
For optimal growth, bloom production, and quality, fertilize three times: In early spring when plants are just leafing out. In early May to boost their flower production for summer. In late June/early July to help your plants finish the summer strong.
Balanced granular fertilizers such as Espoma Rose Tone and Holly Tone are good choices. Jobes Fertilizer Spikes are another good option. Avoid using fast-release fertilizers in liquid form on hydrangeas. These products can stimulate growth in the short term but may not sustain the plant for the long haul.
If you over-fertilize, it can burn the root system of your hydrangea bushes and actually inhibit bloom production. For more tips on fertilizer and how to achieve big, beautiful blooms, please click here. My hydrangeas have brown dry spots on the leaves and brown petals on the bloom.
Miracle-Gro Performance Organics Blooms Nutrition
This is an all-purpose blossom booster that's suitable for use on a wide variety of perennial and annual blooming plants, including hydrangeas.
If you are looking for an all-around great option for hydrangeas and other flowers then I recommend the Miracle-Gro All Purpose Plant Food. This fertilizer instantly feeds providing bigger, better fruit. You can apply it every two weeks with a garden feeder.
Also, when you do water, after a week or 10 days, water with a water soluble fertilizer such as Miracle Grow, Rapid Grow or Peters 20-20-20. Apply this water soluble fertilizer every second or third watering and see if the plant doesn't do better.
Keep this in mind as your choosing and caring for your plant. Requirements: in this area hydrangeas prefer full morning sun with afternoon dappled shade. They like well-drained, moist soils. Fertilizing: recommended granular, slow-release fertilizer of 10-30-10, in the spring/early summer.
Supply the Right Amount of Water. Along with planting them in the right place, properly watering your hydrangeas is essential to bigger and better blooms. "Hydrangeas should be watered deeply several times per week to encourage deep root growth," says Enfield.
To prepare hydrangeas for winter in colder areas, add a thick layer of mulch around the base of the plants to protect the crown and roots from freezing temperatures.
While some plants bloom on new growth, others primarily set flower buds on old wood. Regardless, it is best to wait to prune all hydrangeas until spring. In the fall, hydrangeas (and all trees and shrubs) are in the process of going dormant. They do not produce very much new growth until the following spring.
To reduce the size of a hydrangea that blooms on new wood, cut off about one-third of each stem in late fall or early spring before it begins to leaf out. If your hydrangea blooms on old wood, prune right after it has bloomed when the flowers are fading.
Some gardeners report success in turning their hydrangeas blue by applying coffee grounds to the soil. The coffee grounds make the soil more acidic, allowing the hydrangea to more easily absorb aluminum. In addition, fruit peels, lawn clippings, peat moss and pine needles, are thought to have a similar effect.
Potted hydrangeas overwinter best in a garage or basement where the temperature stays cool but doesn't freeze. The plants will go dormant, but you'll still need to water the pots occasionally, about once a month, to keep the roots moist, until spring.
Prune back stems to just above a fat bud — called a heading cut — in fall, late winter or spring. These plants have conical-shaped flower heads. I recommend leaving the dry, tan flower heads on the plant to provide some winter interest in your landscape, so I wait to prune these until late winter or spring.
Hydrangea blossoms are at their best when they are well watered and well fed. Mulch also provides an evaporation barrier. Keeping your soil moist in the heat of the summer, which is also the flowering season for hydrangeas, will help to maintain the healthiest version of your plant.
Fertilization. Fertilize your Endless Summer Hydrangeas in the spring with Holly-tone for blue flowers or Plant-tone and granulated lime for purple to pink flowers. For best flowering we recommend fertilizing in April, May and June with 1 cup of fertilizer for each foot of branch spread.
This common household item is surprisingly effective at helping perk up plants and brighten blooms. For hydrangeas specifically, adding baking soda helps the plant retain more moisture in the roots. When this happens, the result is bigger blooms with more vibrant colors that last longer than they would otherwise.
Once you've established your vinegar solution, pour it around the base of your hydrangea, thoroughly soaking the soil while avoiding the stalk, stems, and leaves. Repeat these steps every two weeks, and within a few months, you should notice the blooms start to blue!
Use a fertilizer low in phosphorous (the middle number in the content analysis) such as 12‐4‐8 to encourage production of blue flowers. For other types of hydrangeas, use a general purpose fertilizer, at recommended rates on the package. Incorporate dry fertilizer into top 2” – 3” of soil and water thoroughly.