Your Hanging Baskets Will Explode With Blooms – and Last Longer – If You Do This Just Once a Week
Regular summer feeds give hanging basket plants the nutrients they need to bloom
Life isn’t always easy if you are growing in a hanging basket. Flowering plants put huge energy into their summer display, but there are only so many nutrients available to them in the limited soil. They need a helping hand. To give the plants what they need, it is advisable to feed baskets weekly with a liquid fertilizer.
When it comes to identifying the best fertilizer for hanging baskets in the summer, those sold as a ‘bloom booster’ or a tomato feed are the two top options. This is because they are high in phosphorus and potassium, which encourage flowering, and they come in liquid form to deliver nutrients fast.
There are many different feeds to choose from, but Jack’s Classic Blossom Booster, available at Amazon, must rank among the best fertilizer for hanging baskets. If you feed your hanging basket plants with it weekly, you’ll have a plentiful display to enjoy all summer long.
What Is the Best Fertilizer for Hanging Baskets in Summer
Classic summer hanging basket staples, like petunias, geraniums, trailing fuchsias, and million bells, are hungry plants that need lots of essential nutrients during the season to keep blooming and putting on a showstopping performance.
When planting in a hanging basket, it is beneficial to add some balanced, slow-release fertilizer to the mix to give a solid base of nutrients for the first few weeks of development. Use a product like this organic all-purpose granular plant food from Burpee.
However, due to the limited soil in the hanging basket, the plants can quickly use all the available nutrients. Then it becomes vital to fertilize flowers in pots and hanging baskets regularly throughout the season. A regular feeding routine ensures plants have a continuous source of nutrients so they can flower for as long as possible.
The best habit to adopt is to use a water-soluble, high-potassium plant fertilizer weekly once your hanging basket plants start blooming.
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Why a liquid fertilizer in this instance, you may ask. Liquid fertilizers release nutrients quickly to plants, which is key as your hanging basket plants are hungry in summer.
They act fast, but they don’t last long. This is why using them regularly (ideally weekly or at least every two weeks) is the easiest way to guarantee plants have a consistent supply of nutrients to keep flowering.
An ideal liquid fertilizer for hanging baskets will be rich in potassium, often referred to as potash. This particular nutrient keeps plants healthy and improves the quality and number of blooms.
Phosphorus is also important for flowering plants during summer, as it is the nutrient responsible for developing new buds, but less nitrogen is needed. Giving hanging basket plants too much nitrogen will result in lots of foliage but not many blooms to enjoy.
Jack’s Classic Blossom Booster has an NPK ratio of 10-30-20. It contains lots of phosphorus to set buds and potassium to increase bloom size and quality. That double whammy guarantees you a stunning display of flowers in your hanging baskets all summer long.
Apply it every week or two by mixing one tablespoon of feed with a gallon of water – the product helpfully comes with a measuring spoon, so you avoid overfertilizing plants. And you apply it when you water plants, so it is easy to incorporate feeding hanging baskets into your summer routine.
Alternatively, tomato fertilizer makes an excellent fertilizer for hanging baskets, too. Many plants benefit from tomato feed; it is not just tomatoes that such products are limited to.
Such products are high in potassium, making them perfect for hanging baskets and any flowers in containers. You can extend the flowering of annual flowers in baskets with a weekly dose of tomato feed, such as this concentrated tomato booster fertilizer at Walmart, which has an NPK of 3-8-7.
Shop More Fertilizers for Hanging Baskets
This bloom booster can be mixed in a watering can and used on plants, or you can use it with the Miracle-Gro garden feeder (also available at Amazon).
FAQs
What Is the Best Slow-Release Fertilizer for Hanging Baskets?
Some fertilizers can feed hanging baskets for longer than others. If you want a granular product that lasts more than just a few weeks at the start of the season, consider the Osmocote Smart-Release Plant Food, available at Amazon.
This granular feed claims to supply nutrients for six months. In reality, this is likely to be reduced in a hanging basket as regular watering leaches nutrients from the soil more quickly than in the ground.
Another key summer maintenance task to guarantee your hanging baskets bloom for longer is deadheading. Taking time to remove spent blooms encourages more buds and flowers to develop, extending the flowering display.
Self-cleaning annuals like petunias, impatiens, and begonia will shed old blooms themselves, but other hanging basket flowers can be deadheaded using a pair of pruning snips (I particularly like these Felco pruning snips, available at Amazon) or by removing old flowers with your fingers.
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Drew has worked as a writer since 2008 and was also a professional gardener for many years. As a trained horticulturist, he worked in prestigious historic gardens, including Hanbury Hall and the world-famous Hidcote Manor Garden. He also spent time as a specialist kitchen gardener at Soho Farmhouse and Netherby Hall, where he grew vegetables, fruit, herbs, and cut flowers for restaurants. Drew has written for numerous print and online publications and is an allotment holder and garden blogger. He is shortlisted for the Digital Gardening Writer of the Year at the 2025 Garden Media Guild Awards.