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How To Fertilize Geraniums – Keep Your Geraniums Flowering Big

Want to know how to fertilize your geraniums to keep them flowering big and strong all summer long?

Geraniums are one of the most iconic flowering annuals of all. The versatile plant is a top choice for bringing life all over the landscape – from flowerbeds, gardens and raised bed plantings, to hanging baskets, containers and more.

But as popular as they can be to grow, geraniums can also be a source of major frustration for quite a few gardeners. Especially when it comes to keeping them blooming strong for an entire growing season. All too often, geraniums that were full of blooms in mid-May fade into a flowerless mass of weak foliage by mid summer.

how to fertilize geraniums
It’s hard to beat the beauty of a geranium when in full bloom!

Is it a lack of water? Perhaps not enough sunlight? The simple truth is that although proper light and water can indeed play a major factor in the bloom production of geraniums, more often than not, the flowering annual struggles to bloom due to a lack of nutrients.

Feeding Geraniums – How To Fertilize Geraniums

As an annual, geraniums need a steady supply of nutrients to power bloom sets on a continual basis. When first planted, there are usually enough nutrients in the soil for strong growth. But as the season progresses and the geraniums begin to grow larger, those resources can begin to disappear quickly from the soil.

This can be especially true when geraniums are growing in pots or containers where there is a limited amount of soil. Even when planted in the most fertile of potting soils, the geraniums will eventually use up the available nutrients. And when they do, it becomes harder and harder for them to bloom.

This is exactly where fertilizing can save the day – as long as it’s the right type of fertilizer! And when it comes to keeping geraniums blooming at peak performance, it’s all about balance.

To produce new stems and bloom sets, geraniums need a balance of nutrients. If a fertilizer is too high in nitrogen, it can cause the plant to grow bigger, but not produce more blooms.

Most fertilizers consist of three major nutrients – nitrogen, phosphorous and potassium. And each of the “Big Three” have an equally important role to play in a geranium’s overall health and growth. Nitrogen helps spur growth. Phosphorous aids in cell development and bloom production and potassium helps with water balance and health.

What Geraniums Need To Flower – How To Fertilize Geraniums

For geraniums, the biggest key is to not give them an overabundance of nitrogen. Nitrogen is an important nutrient for plants, but it helps more with overall growth than blooms.

With geraniums, nitrogen works to help the plant to grow larger and produce deep green foliage. It can certainly make the plant look incredibly healthy, but when it gets too much nitrogen, it will simply try to only grow larger – and at the expense of forming new blooms.

Instead, it is far more important to fertilize geraniums with a power source that contains an equal balance of nitrogen, phosphorous and potassium. By giving all three in equal amounts, the plant will respond with good growth, good health – and yes, more blooms than ever!

jacks geranium fertilizer
The best fertilizer for geraniums is a water soluble product that contains an equal percentage of nitrogen, phosphorous and potassium.

The phosphorous will help by generating more blossoms – and the potassium will aid greatly in water management. Meanwhile, the equal serving of nitrogen will help keep the plant growing strong, but without too much power. See: Understanding N-P-K – Selecting Fertilizers

Using A Water Soluble Fertilizer

In addition to selecting a power source that is balanced, the second key to success when fertilizing geraniums is to make sure your fertilizer is water soluble.

Although granular fertilizers will slowly work into the roots of plants, liquid fertilizing can work both through the roots of plants and by absorbing through the leaves. And even better, it can do it quickly! For geraniums, by simply giving them a dose of liquid energy every two weeks, you can all but ensure great blooming all season long.

For best results, use a balanced liquid fertilizer in the 10-10-10 to 15-15-15 range for its N-P-K makeup. This will provide the perfect balance of power without overpowering your plants. Product Affiliate Link : Jack’s Geranium Fertilizer

Additional Blooming Factors – How To Fertilize Geraniums

When it comes to keeping your geraniums flush with new blooms, in addition to giving them a strong and steady source of power, there are a couple of additional tips that can go a long way towards success – the first of which is deadheading.

Allowing the old flower heads to remain on your plants will impact future blooms. And not in a positive way! Decaying flowers and stems on geraniums drain power from the plant. And as long as they remain, your geranium will continue to expend resources on trying to fix them.

By simply cutting back old blooms, you can stop the flow of wasted nutrients and redirect the plant’s efforts towards creating and opening new blooms.

cutting back geranium blooms
Allowing old geranium blooms to remain on the plant will delay future blooms. The quicker you prune back spent flowers, the faster the plant will produce new buds.

It is important when deadheading to remove more than just the flower petals. With geraniums, be sure to cut the stem back as well all the way to its base. This will go below the canopy of foliage. Not only will it keep your plant looking neat and tidy, but it will stop the entire amount of energy being wasted to the old bloom.

Don’t Overwater – How To Fertilize Geraniums

When it comes to geraniums, overwatering is almost always a bigger issue than underwatering. When they get too much water, the leaves of geraniums plant will begin to yellow. Unfortunately, many gardeners take this as a sign the plant must need more water and compound the problem even more.

When geraniums become waterlogged, their roots swell. When this happens, they cannot take in nutrients or moisture. And without energy, the plant will slow or even completely stop attempting to create new blooms.

Only water your geraniums when the soil dries down a few inches in the soil. If you have a soil moisture meter, anything more than a 25% moisture reading means you should hold off on watering. In addition, it is more important to water deeply than more often.

This will allows roots to go deeper in the soil as opposed to staying at the surface where they are more vulnerable. Here is to fertilizing your geraniums for success – and to more blooms than ever this year!

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