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How To Keep Marigolds Blooming All Summer – 4 Secrets To Big Blooms!

Want to keep your marigolds blooming big and strong all summer long? With just a few simple tips, you can have your marigold plants growing wild with flowers right up until the first frost!

Marigolds are hot again among gardeners, and with good reason. This durable annual flower with gorgeous blooms is more than just a showy plant for flowerbeds, pots and baskets.

Not only can it stand up to the rigors of heat, humidity and full sun, it can also be a valuable asset for repelling common pests and insects that can affect flowers, vegetables, and humans as well.

fertilizing marigolds to keep them blooming
Marigolds can be found in a wide variety of blooming styles. These massive pom-pom style blooms are a great way to add a huge pop of color to containers and bed spaces.

Marigolds are a well known companion plant in the vegetable garden. When planted near vegetable plants like tomatoes, peppers and cucumbers, they can help repel aphids, whiteflies, tomato hornworms and more. But they also happen to be an incredible weapon against mosquitoes too.

The Many Benefits Of Growing Marigolds – How To Keep Marigolds Blooming

The pungent odor of marigold blooms is highly offensive to mosquitoes. In fact, so much so that they stay far away from areas where this flowering annual grows.

When planted in flowerbeds and containers near outdoor gathering spaces, marigolds can be a great first line of defense against mosquitoes. (See: How To Keep Mosquitoes Away From Your Patio & Yard – With Plants!)

french marigolds
Marigolds scent is well known to repel mosquitoes. French marigolds, pictured above, are one of the best choices of all for repelling mosquitoes as well as many other types of common insects & pests.

But maybe the best benefit of growing marigolds is that they can add stunning color anywhere. From smaller varieties like Queen Sophia and French marigolds, to plants with massive blooms like Cracker Jack marigolds, they can fill any space with huge color. Especially when you can keep them blooming strong all summer long.

Here is a look at how to get the most from your marigolds and keep them blooming and booming well into late fall.

4 Simple Secrets To Keep Marigolds Blooming Strong All Summer

#1) Deadheading Old Blooms

At the top of the list is deadheading! If there is one thing that can hold your marigolds back from continuous flowering, it’s leaving the old blooms in place.

Fading flowers take valuable nutrients and resources from marigold plants. If left on, the plant will continue to attempt to heal and power the decaying flowers. And in the process, keep from producing new blooms and future flowers.

deadheading marigolds
Allowing spent flowers to remain on the plants will take away resources from the plant that should be going to create new blooms. Regular deadheading of old blooms will significantly increase flower coverage for the plant.

To keep your plants in continual blooms, practice regular removal of fading blooms. And with marigolds, its easy! Simply pinch of the blooms behind the flower with your fingers to remove.

Sharp scissors will work, but marigold blooms will peel off easy with just a pinch. The more you pinch back old flowers, the more you will be rewarded with more and more new blooms!

#2) Fertilizing Marigolds – How To Keep Your Marigold Blooming Big

When it comes to keeping plants in full bloom, fertilizing properly is a close second to deadheading. Producing new blooms and flowers requires a lot of energy from plants. Especially when plants are continually trying to regrow new blooms all season long.

And that is exactly why feeding your plants regularly is so important! But total success also depends on how you provide the nutrients to your marigolds. A steady, slow stream of power is far better than large intermittent doses.

cracker jack
Marigolds, like all annuals, require a lot of nutrients to continually produce blooms. But by providing a slow and steady supply instead of large single amounts, you can keep plants blooming strong all summer long.

Heavy applications of fertilizers can provide too much power too quickly to your marigolds. It will result in a mass of growth, but can create overgrown root structures. That can lead to crowded roots, and a plant that produces more foliage than blooms.

For best results, fertilize your marigolds every 10 to 14 days with one-quarter to one-half of the normally recommended dose of your favorite flower fertilizer. This will allow plants to keep a steady but manageable supply of nutrients to power blooms continually.

Liquid fertilizers are the best choice when it comes to powering annuals like marigolds. The nutrients are quickly absorbed and put to use.

In addition to commercial liquid fertilizer mixes, compost tea and worm casting tea are excellent choices to power plants. They are well balanced, and are quickly absorbed by plants.

#3 Provide Support For Taller Marigolds

Smaller varieties such as french marigolds are more than fine to grow on their own, but if you are growing large varieties like Cracker Jack or Pom Pom marigolds, it is important to give them a bit of support with small stakes.

fertilizing cucumber plants
Worm castings can be used to make an excellent fertilizing tea for plants. You can also sprinkle a quarter cup of castings around plants to act a slow release fertilizer.

Allowed to grow on their own, these larger varieties often crack and split under the weight of their own branches and blooms. And when this happens, plants end up spending more energy on healing than producing new blooms.

It doesn’t take much, a few small wooden dowel rods placed into the soil and tied to the plants will work wonders in keeping plants steady.

#4 Water Smart – How To Keep Marigolds Blooming Big

Finally, when it comes to keeping marigolds blooming strong, proper watering is a must. Marigolds need moisture to power blooms and soak in nutrients through their roots and foliage.

For maximum blooming, marigolds growing in bed spaces should get at least an inch of water per week. Either by rain, or by watering.

watering annuals
Proper watering is important to keep marigolds producing new blooms. Infrequent watering, or allowing plants to dry out too much in between, creates additional stress that can delay or stop new bloom cycles.

How much is an inch of rain? On average, a solid 30 to 60 minute shower twice a week is adequate. When watering by hand, a half gallon of water per plant twice a week is close to being equal to that amount.

For containers, pots and hanging baskets, daily watering is likely a necessity. But be careful not to overwater. The roots of marigold plants can be susceptible to rot when left to sit in water.

Check the soil in containers by sticking the tip of your index finger down about an inch into the soil. If it is moist or wet, avoid watering. If it comes up dry, give the plants a dose of H2o.

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Here is to keeping your marigold plants healthy, strong and blooming like crazy all summer long! For even more on marigolds, check out our article on our sister site : The Ease, Beauty And Benefits of Growing Marigolds In The Garden. Happy Gardening! – Jim and Mary.

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