Coffee Grounds And Hydrangeas

While many people love their hydrangeas, they often would love them even more if they were blue. Luckily the grounds from your morning cup of coffee can help you to achieve those gorgeous blue blooms. Here’s what you’ll need to know about coffee grounds and hydrangeas.

Hydrangeas And Soil pH

Unlike most other types of plants, the flower color of hydrangeas can depend on the pH of the soil. Hydrangeas in alkaline soil will have flowers that are pink or sometimes red. Those which are planted in acidic soil will have flowers that are blue. And in neutral soil plants often produce flowers that are a mixture of pink and blue, or purple.

Coffee: A Natural Choice

Unfortunately, the color of white hydrangeas can’t be changed to any other color but you can change pink, red, or purple flowers to blue. And coffee can help you do it. Coffee grounds often maintain a slight level of acidity even after being used to make your morning cup of coffee.

They therefore can function as an all-natural and free way to make your garden soil more acidic. By using coffee grounds in the garden instead of sending them to your local landfill with the rest of your trash you’ll also be helping the environment one cup at a time.

Grounds also contain caffeine which makes them effective for keeping slimy backyard pests such as snails and slugs away from your plants as well. Since they have a high level of nitrogen many gardeners actually use coffee grounds as fertilizer for hydrangeas along with other plants too.

Getting Started With Coffee Grounds And Hydrangeas

You may want to invest in a soil pH test or simple pH meter so you can see just how acidic or alkaline the soil you are working with really is before getting started. They can also help you to track your progress and draw more accurate conclusions about your efforts. To grow blue flowers you’ll ultimately want your soil to have a pH of 5.2-5.5.

When adding your grounds make sure they have cooled down to room temperature and then you can simply place them on top of the soil around the base of your plants. You can also mix them in with the soil if you prefer a neater look. Because they retain water, the coffee grounds can help to keep your soil moist in-between watering, which hydrangeas like.

Another option would be to place them in a cup, add a bit of water, give them a quick stir and then pour the mixture onto the soil. You can also put your coffee grounds in the compost bin and then add then amend your soil with the finished compost every six months or so.

How Long Does It Take?

Like most natural processes, changing the color of your blooms takes time. So don’t expect changes overnight. Typically you can expect your flowers to change color over the course of a growing season. If your plant has not yet flowered at all, you’ll need to wait for your plant to mature a bit. Hydrangeas generally need to be at two or three years of age before they produce flowers.

Other Options And Ways To Go

You don’t have to use coffee grounds for blue hydrangeas. Other alternatives include adding pine needles, aluminum sulfate, or a soil acidifier. And if you decide you’d like to change your flowers back to pink in the future ground lime or crushed eggshells can help make your soil more alkaline.

Now that you know the relationship between coffee grounds and hydrangeas you can use it to get those blue blooms you’ve always desired.

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