Coffee grounds add extra acidity to the soil around hydrangeas. On a chemical level, this increased acidity makes it easier for the plant to absorb naturally occurring aluminum in the dirt. The effect is pretty blue clusters of flowers.
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.
By altering the soil pH with vinegar, you can actually turn your pink-flowering hydrangeas blue! For this trick, simply dilute your vinegar in water before pouring it around the base of your hydrangeas, and within just a few weeks you could have fresh and bountiful blue blooms.
There are plenty of reasons why your hydrangeas may not be blooming as much as they once did. Conditions like extreme heat, drought, or excessive sun exposure can all impact how many flowers your shrubs produce. Pruning is also an important consideration.
You can use vinegar to lower the pH of your soil, but be aware that in order to achieve blue blooms, you will need both an acidic environment and aluminum ions. The acidic environment will also need to be a sustained over a period of time, which could be hard if rainwater is washing the vinegar away.
It's best to start adding coffee grounds to the soil months before the blooming season begins, ideally in the late fall. You can repeat the process with your typical fertilizing schedule. With a little caffeine and a lot of patience, your hydrangeas should reward your efforts come spring with the boldest blue globes.
Baking soda helps reduce soil acidity and increase the pH levels needed for these flowers to blossom into a deep shade of red.
If you want pink hydrangeas, crushed eggshells may be one way to get them. Eggshells will slowly break down and reduce the acidity of your soil—making it harder for hydrangeas to absorb aluminum.
Hydrangea Care Tips
Water at a rate of 1 inch per week throughout the growing season. Deeply water 3 times a week to encourage root growth. Bigleaf and smooth hydrangeas require more water, but all varieties benefit from consistent moisture.
Best Fertilizer For Hydrangeas
Organic, slow-release fertilizers for roses (such as a 15-10-10, or 10-5-5 formula) work well on hydrangeas, giving the plants the nutrients they need to increase the size and quantity of their blooms.
Homemade compost is a great source of slow release nutrients for hydrangeas. Either top dress the soil beneath your plants with your compost and water well or brew up a batch of compost tea and give your plants a deep drink of it. You can repeat your application of compost tea in 2 to 3 weeks.
Typically hydrangeas thrive when fed an all-purpose, balanced fertilizer like a 10-10-10 N-P-K or 12-4-8 N-P-K.
If your soil is more alkaline, your hydrangeas will be pink or even purple. According to Garden Design, adding lime or eggshells to the soil will ensure a pinker color, while adding aluminum sulfate, pine needles, or coffee grounds can give your hydrangeas the blues.
Coffee grounds are rich in nutrients, especially nitrogen. They also have some amount of other nutrients like potassium and phosphorous. Overall, this means that adding coffee grounds to your garden can work fairly well as a fertiliser. Coffee should be spread in a thin layer, rather than being clumped in one place.
If your hydrangeas do get infected, you have several easy, effective, and homemade options. You can dilute either hydrogen peroxide or garlic oil in a spray bottle and spray it directly on the affected leaves.
First, add a 1/4 cup of sugar to the room temperature water in the vase. The sugar helps feed the stems and increases the life of the cut flowers.
A Little Goes a Long Way. Baking soda is the secret, but keep in mind that a little bit does go a long way. To apply it to your wilted hydrangeas, mix 1 tablespoon of baking soda into 2 quarts of water. Stir to be sure the baking soda thoroughly dissolves.
If you don't prune hydrangeas then they can eventually resemble a tangled mass of woody stems, and the flowers will become smaller and less showy.
If you have sandy soil, add some compost to the ground to help the soil retain water. Topping off your gardens with mulch is another great way to help your soil retain moisture. Add your mulch at any time of the year; I prefer to mulch in mid-spring. If your hydrangea is overwatered, check your soil.
Bigleaf Hydrangeas: Bigleaf Hydrangeas are the most popular type of Hydrangeas. They begin blooming in late May or June in warmer climates and later in the summer in cooler climates. Some Mopleaf varieties are remontant, meaning that they bloom twice in a season.