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How To Keep Petunias Blooming Strong – 3 Simple Secrets To Success!

Want to keep your petunias blooming strong, beautiful and vibrant all summer long? Believe it or not, it really is possible by employing a few simple growing tips that work like magic!

Petunias are one of the most popular summer annuals of all for growing in flowerbeds, containers and hanging baskets. From trailing varieties, to wave petunias and more, they can be found in a near endless variety to fill almost any need or space. Especially when you consider their wide range of colorful blooms!

But, as with many annuals, gardeners often find their petunias beginning to struggle by mid-summer. Plants once covered completely in blooms and flowers begin to have trouble just keeping their foliage from turning brown.

keep petunias blooming
Petunias add big color and texture to any setting. With a full range of single, double and variegated bloom styles, they compliment any setting. Above, trailing petunias flow over the pots as a perfect companion to additional annual plantings.

Sadly, within a few weeks of the first signs of trouble, without help, plants simply wither away. The good news is in almost all cases, it simply doesn’t have to turn out that way!

In fact, when it comes to keeping petunias thriving all summer long, 3 simple secrets really can make all the difference between throwing your plants out in mid-summer, or enjoying their blooms into late fall!

3 Simple Secrets To Keep Petunias Blooming All Summer

#1) Fertilize – Slow, Steady & Consistently

More than anything else, petunias need a slow and steady diet of nutrients to keep producing blooms and flowers.

As a heavy flowering annual, petunias quickly deplete the resources available in the soil around their roots. And without replenishing those nutrients, they will inevitably begin to slowly weaken over time.

keep petunias blooming
In order to keep petunias blooming, you need to supply them with energy. Not only will fertilizer help them continue to grow good foliage, but it will also help the plant produce more blooms and flowers.

But the secret key to long term success is how and when you replenish those nutrients. Unfortunately, many fertilizers provide too much power too quickly. Especially when they are over-used.

This might result in massive blooms and growth at first, but spells big trouble for the plants over time. Plants that grow too fast with a massive burst of nutrients are like a shooting star. Brilliant for a moment, but quick to fail and die out not long after their show.

Fertilizing Right

All of that power leads to too much growth too fast. And it is simply not sustainable for the plant. Especially when there is limited soil space in container and basket plants.

And that is where the slow and steady approach works wonders. Because of this, it is far better to feed your petunias (and all annual flowers for that matter) with a light but consistent feeding.

If you are using a high quality liquid or granular all-purpose fertilizer, dilute the solution to 1/4 or 1/2 of the recommended dose and apply every 10 to 14 days. Even better, use compost tea or worm casting tea weekly to provide a more balanced dose of power to your plants.

perennial fertilizer
Using an all-purpose fertilizer in smaller doses is a great way to keep plants blooming strong, without the worry of overgrowth. Too much energy can actually shorten the overall lifespan of your petunias.

Remember- it’s far better to give them a slow and steady boost of nutrients to keep them in top shape – in place of that quick burst that can send plants into a frenzy.

#2) Deadheading Old Blooms – How To Keep Petunias Blooming All Summer

Not only do old blooms look unsightly on plants, they also can rob it of vital nutrients. As with most annuals, petunia plants continue to spend resources attempting to heal and fix old blooms. Resources that instead could be used for producing new blooms and flowers.

Deadheading (the process of removing spent flowers) your petunias is one of the best ways of all to keep those flowers coming on.

By simply taking off the older blooms that are beginning to fail, the plant can concentrate all of it’s energy on growing healthy foliage and more flowers. And it couldn’t be easier to do!

Check out our Podcast on How To Keep Hanging Baskets Blooming!

Petunias happen to be one of the easiest of all annual to deadhead. There is no need to cut stems or use tools of any kind. Simply give a slight pull to an old flower and it instantly dislodges from the plant.

It’s actually quite therapeutic to do! Deadhead your plants every few days and you will be amazed at how much energy the plant retains throughout the growing season.

#3) Give Them Room To Grow – How To Keep Petunias Blooming All Summer

And finally, if you want your petunias to keep on flowering all summer long – you have to give them room to grow. And by room, we are talking about soil space for their roots.

Plants draw and take in nearly all of their nutrients and water from their roots. And if there is little to no soil for them left to expand, the plant will begin to fail. No matter how much you try to feed or water it!

Although good soil for ground planted petunias is important, this is especially vital with container and hanging basket petunias. By mid-summer, many container plants simply run out of soil for roots to expand and grow.

repotting a petunia
When a plant becomes root bound, it is time for re-potting. Either place into a larger container, or plant it directly into a flowerbed.

Have you ever went to water a plant in mid-summer and watched the water instantly roll through the bottom? It is most likely the result of a root bound plant. Meaning, the roots have expanded so much, they can no longer find a way or the space to grow.

Re-Potting Petunias – How To Keep Petunias Blooming All Summer

The only remedy for this is to replant your petunias into a larger vessel, or into the ground so they can expand. And the quicker you do it, the more chance your petunia plants will have to keep on blooming!

When replanting, always try to select a vessel that is 2 times as large as the original. This will allow plenty of space for the petunias to stay strong for the remainder of the season.

And if your plants are simply too big for a new pot or basket? Why not plant them directly into a flowerbed! You will be amazed at the renewed energy and life the petunias will have from new soil.

Here is to keeping your petunias blooming strong and vibrant all summer long! Happy Gardening – Jim and Mary.

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