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Fertilizing Petunias – How To Get Petunias To Bloom Big All Summer!

Whether you grow petunias in hanging baskets, containers, or directly in your flowerbeds – to get your plants blooming big and keep them flowering strong all summer long – fertilizing is a must!

Petunias are one of the most popular of all summer blooming annuals. Not only do the plants produce large amounts of bright, funnel-shaped blooms, they do so in wide range of colors. In fact, with each passing year, growers seemingly come up even brighter hues that are nothing short of spectacular!

But what really makes petunias incredible is just how versatile they are. Wherever and whatever you want to grow them in, there is a variety to fit and fill almost any space or need.

fertilizing petunias - how to keep petunias blooming big
The trailing pink petunias are perfect for cascading down in pots or hanging baskets. One of the reasons petunias are so popular is there are so many ways to plant them!

There are compact and smaller vining petunias that are perfect for growing in pots, containers and baskets. And for more spacious flowerbed spaces, there are trailing and spreading varieties that can grow to fill massive areas with a full wave of continual color. That is – if you can keep them blooming!

Getting Petunias To Stay In Bloom – Fertilizing Petunias For Success

If there is one common issue that many gardeners face with petunias, it’s getting their plants to stay flowering strong late into summer and fall. Although petunias are usually thriving and full of color in late spring and early summer, all too often, the plants show early signs of wear and tear as they begin to age.

More times than not, the issue isn’t with the plant. Nor is it from disease or pest issues. Instead, when petunias begin to slow their blooming and begin to fade, the problem can usually be traced back to a simple lack of available energy in the soil.

Petunias require a lot of nutrients to power all of their bright, colorful blooms. Because of that, they can deplete even the best potting soil or flowerbed soil of those nutrients quite fast. And once it’s gone, it doesn’t take long for the foliage and pretty blooms to begin to suffer.

The good news is by simply providing your plants with the right dose and type of fertilizer on a consistent basis throughout the growing season, you can avoid the issue with ease. And in the process, have your petunias blooming big right up until your first hard frost or freeze!

fertilizing petunias
With the right fertilizer, you can power your petunias to blooms like these all season long!

Fertilizing Petunias For Big Blooms That Last!

One thing is for sure, how, when and what you fertilize your petunias with all make a big difference in just how well your plants perform all season long.

If you give petunias too much power all at once, it will actually harm the plants and their blooming potential. When annual flowers (and vegetable plants) get too much energy, they change their growth pattern. Instead of using it to produce more flowers, they use the energy to simply grow bigger.

Likewise, if they get too little energy, or have too much of a delay between feedings, they will also slow or stop blooming. Because of this, it’s important to supply your plants with a consistent but low dose of energy. Even more, it’s also vital to give it to them in a form they can easily and quickly absorb.

Why Liquid Fertilizer Is The Best Choice For Powering Petunias

Without a doubt, when it comes to energizing petunias, liquid fertilizers are the way to go. Liquid fertilizers are able to absorb into plants in two separate but powerful ways. And that double action is a huge help in keeping plants continually blooming!

When a liquid fertilizer is applied to the soil around a plant, it soaks down into the roots. Because it is in a liquid form, the roots are able to absorb it quickly. This allows the plant to use the power almost immediately.

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But liquid fertilizers also absorb into a plant through its leaves and stems. As the liquid touches the foliage, it absorbs in through the cells of the plant. This provides an additional source of energy that doesn’t have to take time to come through the roots.

Another big benefit of using liquid fertilizers vs. granular is that with liquid power, you can easily adjust the level of strength. And that makes delivering a perfect “low and steady” dose of energy much easier. And that low and steady approach is the perfect prescription for healthy plants that overflow with blooms!

So what are the best liquid fertilizers to use? In that department, you have a couple of great options. It all really depends on whether you want to purchase a ready-to-go commercial option that you mix with water, or create your own powerful liquid from compost or worm castings.

Here is a look each of the three options – and how to apply them for strong flowering all season long.

Liquid Commercial Fertilizer – Fertilizing Petunias For Success

When looking for a liquid fertilizer to power your petunias, look for options that have equal or higher amounts of phosphorous in the nitrogen-phosphorous-potassium (N-P-K) ratios listed on commercial fertilizers. This will help more with producing blooms than just plant growth.

bloom booster for petunias
A higher middle number in the N-P-K ratio will power blooms – and not just plant growth.

Plants use nitrogen for growing strong stems and foliage. But it is phosphorous that powers blooms. And by selecting a fertilizer that is equal or higher in phosphorous to nitrogen, you are providing your plants with just the right energy for more flowers.

As for the final number in the equation, an equal or higher number in potassium is great too. Potassium also helps with blooming and plant health. See: Understanding N-P-K Ratios – How To Select The Best Fertilizer For Plants

Many fertilizers now designed for better blooming will have the words bloom and booster right on the package. A balanced fertilizer will work as well (10-10-10, 15-15-15), but if you can find one with a higher middle number (phosphorous), it is the better choice.

Once you have your fertilizer, the next key is to dilute it when making to one-half of the recommended dose. By weakening the solution, you keep the plant from getting too many nutrients all at once. This also allows you to give the plants a dose more often to keep a steady supply of energy.

For best results, when fertilizing with a commercial fertilizer, use at half-strength every seven to 10 days. This is the perfect balance of giving great nutrients with a low and steady method. Affiliate Link: Jack’s Bloom Booster 10-30-20

Compost Tea – Fertilizing Petunias For Success

If you want a homemade option for powering your petunias to bigger blooms, it’s hard to beat compost tea. Compost tea has all of the natural nutrients your petunias will need to bloom big – and in just the right amount!

Compost tea is also easy to make at home, whether you use your own homemade compost, or purchase bags of compost at the store. To make, fill a five gallon bucket 1/3rd full of compost. Next, add water to within a few inches of the top.

Stir your mix a few times each day and allow the mixture to brew for three to five days. Strain the liquid from the compost, and you are ready to water your plants with liquid gold!

compost tea
Compost tea has a perfect balance of energy to power your petunias to strong flowering.

You can fertilize with compost tea at full strength every seven days. The nutrients will not overpower your plants, but will provide excellent energy for strong healthy growth and big blooms. Compost tea is actually great for all flowering annuals and your vegetable plants as well!

Worm Casting Tea – Fertilizing Petunias For Success

Much as with compost tea, worm casting tea is made by soaking pure worm castings in water. To make for petunias, soak one cup of castings in one gallon of water. Shake or stir the water a few times each day for two to three days. Then, strain out the castings and water your plants with the tea.

The nutrients in worm castings are pure and easy to absorb – just like compost. They will quickly go to work to help power steady growth and more blooms. Water with casting tea every seven days for best results. As with compost tea, there is no need to dilute the concentration.

Here is to powering your petunias to new heights and better blooms than ever this year – all with a little steady dose of liquid energy!

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