Fertilizer for Petunias: Comprehensive Guide to Successful Blooms

Wave Petunias in Hanging Basket: Fertilizer for Petunias Featured

Petunias are some of the most popular flowering annuals due to their beautiful blooms and because of how easy they are to grow. These plants are known for their abundant showy flowers. Petunias are one of the most common flowers that grow in hanging baskets, as they grow tons of cascading flowers that flow over the sides. Due to this vigorous growth, it’s important to learn about fertilizer for petunias in order to successfully grow them. Popular varieties of petunias to grow are Wave, Supercascade, Tidal Wave, Shock Wave and many more!

In This Article

About Petunia Fertilization

Petunias will continue to flower throughout the entirety of the warmer months until the first frost. To keep these heavy bloomers producing continuous flowers throughout the season, it’s important to fertilize them on a regular schedule. This provides them with plenty of nutrients to keep growing successfully. These plants are notorious for being heavy feeders and requiring a lot of fertilization, especially for plants that are grown in containers. Abundant watering of container plants causes nutrients to get flushed out over time and deficiencies to begin if they are not regularly replaced.

How Often Do Petunias Need to be Fertilized?

You should begin your fertilization schedule for petunias 2 weeks after you plant them outdoors for the season. Doing this encourages their early growth and will help them get acclimated to the outdoors properly. As a general rule of thumb, fertilize your petunias once every 2 weeks. For spreading varieties, fertilize them once a week for optimal growth. Alternatively, you may opt to fertilize twice as often at half strength. This would provide your plants will continual nutrients in smaller doses.

Important Nutrients for Petunia Growth

You will find that every fertilizer has an NPK ratio on the container, which gives you vital information about the product. NPK stands for nitrogen, phosphorous, and potassium, which are important nutrients for all plants. Understanding the role of these key ingredients and why they are in fertilizer for petunias is crucial.

  • Nitrogen: Helps with foliage growth of the leaves and vines. This nutrient assists in photosynthesis and keeping a plant healthy.
  • Phosphorous: An important nutrient for root growth, flower development, and nutrient movement.
  • Potassium: Potassium is imperative for overall plant health, color, and stress tolerance.

Start your plants within nutrient rich soil at the start of the growing season. A balanced fertilizer is sufficient for petunias, such as an NPK ratio of 8-8-8 or 10-10-10. This well rounded ratio will ensure that the petunias are receiving an adequate amount of each nutrient. This should work perfectly for maintaining petunias throughout the growing season.

You may also opt for a fertilizer that is specifically designed for petunias during their blooming stage. Many of these fertilizers include iron and other micronutrients that will help a plant from becoming deficient. You will mostly experience this in containers or hanging pots, as nutrients will get washed out over time from watering.

Fertilization Tips for Petunias

Fertilizer for petunias is an important part of growing this flower and promoting healthy growth and blooms. Here are some tips to help you achieve the best results:

  • Package Instructions: Always follow the package instructions on fertilizer for petunias. Many brands have different application guidelines. This will ensure that you do not over or under feed your plants, as well as help you avoid burning them.
  • Application: It’s always best to apply the fertilizer to the base of the plants. Avoid getting the fertilizer on the stem or leaves, as this can cause fertilizer burn on the plant.
  • Watering: Be sure to apply plenty of water to plants after fertilizing to break down the fertilizer and prevent any fertilizer burn.
  • Monitor: It’s important to keep a watchful eye on your petunia plants as they grow throughout the season, especially for container plants. Watch for any signs of deficiencies, such as yellowing of the leaves, lightening of the color, or a lack of production of new flowers. All of this can indicate a deficiency in a certain nutrient.

Best Fertilizer For Petunias

There are many different types of fertilizer for petunias that you can buy. The type of fertilizer that you buy should reflect the condition of the plants. For example, you may opt for a higher phosphorus number to aid your petunia plants in the budding process and get more to grow. Depending on where your plants are at in their health and lifecycle, you may need to adjust your fertilizer choices.

Jack’s Classic Petunia Feed

Jack’s is a well known fertilizer brand and is often recommended for petunias. It has an NPK ratio of 20-6-22 and is specially designed for petunias. Specifically, it is perfect for varieties that grow in containers and hanging baskets. The fertilizer has added iron and micronutrients for hungry plants. This can help address some deficiencies that your plant may be experiencing such as a lack of iron.

For more information check out the company’s website: Jack’s Classic Petunia Feed.

Miracle-Gro Bloom Booster

Another one of the most commonly used fertilizers for flowers is Miracle-Gro Bloom Booster. This mix has an NPK ratio of 10-52-10 and can be used on a wide range of different flowers. This makes it a great choice for a garden with a variety of flowering plants. The high phosphorus levels are meant to boost budding and flowering. It is sure to give you a beautiful display of color from your garden.

For more information check out the company’s website: Miracle-Gro Bloom Booster.

Jack’s Classic All Purpose

This fertilizer is a good example of a balanced fertilizer, as the NPK ratio is 20-20-20. This fertilizer product has plenty of well rounded nutrients for the plant to keep it thriving. You may use this product along side, or later switch to, this brand’s blossom booster fertilizer once the plant shifts into setting buds and flowering.

For more information check out the company’s website: Jack’s Classic All Purpose.

Osmocote Smart-Release Plant Food Flower & Vegetable

This is an excellent choice for a granular fertilizer that will slow release into your soil. Osmocote is a popular fertilizer that comes with tens of thousands of reviews. The NPK ratio of this fertilizer is 14-14-14, making it a balanced all around fertilizer. The application of this product is quite easy. Simply scoop the appropriate amount and sprinkle it onto the soil. Mix the product into the top few inches of dirt and proceed to water your plants regularly! The temperature of the soil controls how the product is utilized by the plants once watered. This makes the product a fool proof way of fertilizing.

For more information check out the company’s website: Osmocote Smart-Release Plant Food Flower & Vegetable.