I’ve had to feed my hanging baskets to keep the plants growing well. But it did take me some research to figure out how often to add the fertilizer.
You should feed hanging baskets once every 2 to 3 weeks during the growing season of spring and summer. You can use water-soluble or slow-release fertilizers in the potting mix. You can feed them more or less depending on the concentration of the fertilizer you are using.
There’s a lot more you need to know when feeding your hanging baskets. I’ve written some information about the different fertilizers, how much is the right amount for your plants, and how to use it for your hanging baskets.
How often should you fertilize hanging baskets?
You can get the fertilizer in granular or liquid form. The instructions provided by the manufacturer will help you understand how often you should add the fertilizer.
There are two stages of plant growth when you can add the fertilizer. The first stage is when you’re preparing the soil for the hanging basket. You can mix the granular slow-release fertilizer into the potting soil just once.
This fertilizer will be released into the soil when you water it. The slow-release fertilizer will last in the soil for a few weeks after germination.
The second stage where you can add fertilizer to your hanging baskets is when the seedlings have started growing.
As a thumb rule, a granular slow-release fertilizer should only be added 1-2 times during the growing season. Liquid fertilizer can be added once every two weeks for the entire growing season.
If you dilute the fertilizer with more water, you can add it every week or even every day. You can use one part fertilizer with 10 parts of water to dilute it.
If you’re using compost tea, it is already diluted and you can feed your hanging baskets every day with it.
The best time to feed the granular fertilizer to the hanging basket is just before watering the plant. The best time to feed the liquid fertilizer is when you’re watering the plant.
How do you know if your plants are over-fertilized?
Crust of fertilizer on the surface of the soil
If you see fertilizer on the surface of your soil, and it hasn’t been absorbed through your soil, then that is a sign you have too added too much fertilizer, or that you have fertilized recently. Most fertilizers are a light color so look like white dust on the surface of your plant.
Yellowing and wilting lower leaves
If the leaves still look fresh and new but have a yellow color this is a sign that there is too much fertilizer in the soil.
If the lower leaves begin to wilt while the rest of the leaves look fine, then this is another sign that you have too much fertilizer in your soil.
Browning leaf tips and edges
The tips of your plants and the edges will look brown if your soil contains too much of a certain nutrient in your soil.
This is easy to spot because the rest of the leaf will be green and new looking, but just the tip or edges will be brown. You can easily break away the brown material in your hands, and it crumbles like pastry.
Leaves falling off
When more leaves fall off than they should it is a sign your plant is trying to maximize leaf production by dropping leaves early. This means that it has more energy for new growth.
But, a plant under these conditions can get ahead of itself and reach an early grave. The roots can’t keep up with the growth above the surface and the plant dies.
This is especially noticeable if a plant drops its leaves in spring or summer when they should be growing their best.
Slow growth of the plants
Many people add fertilizer to increase growth. But, too much fertilizer can stunt growth. This is because the proportion of the different nutrients such as phosphorus and nitrogen isn’t quite right.
Some plants are nitrogen fixers and increase the amount of nitrogen in the soil. Examples of nitrogen-fixing plants are alfalfa, snow peas, and peanuts.
If your soil is already high in nitrogen and then you add nitrogen-containing fertilizer you will unbalance the system and your plants will struggle to grow.
Seedlings don’t grow
If you plant new seedlings into your hanging baskets and they just die. This is a clear sign that your soil is too rich.
You should get a fresh bag of potting mix, and use this instead of the soil you are currently using.
The easiest way is to remove excess fertilizer from the soil is to flush it with water. Use plenty of tap water until it comes out from the drainage holes at the bottom.
Do this again one more time either a few hours later or the next day. You can also transplant the plant into a new potting mix and put it back in its basket.
What is the best fertilizer for hanging baskets?
When talking about the best fertilizer for hanging baskets you want to choose one that has a specific ratio of nitrogen, phosphorous, and potassium, according to Iowa State University. The ideal ratio is 1:2:1 of nitrogen, phosphorous, and potassium. I also prefer liquid fertilizers because they are easy to apply.
One which I like that has this ratio and is organic is the Earth Juice Plant Food. As an added bonus it works on both indoor and outdoor plants. So, if you have to bring your hanging baskets inside, then you can continue to use it, and enjoy big baskets, with lots of flowers.
If you choose a fertilizer that is higher in nitrogen it will make the leaves and stems of your hanging baskets grow faster, but your flowers won’t. This is why the 1:2:1 ratio is better.
For the best results, you should add 1 tablespoon for every gallon (3.8 liters) of water.
Conclusion
You should feed your hanging baskets no more than once every two weeks. Overfertilization can kill your plants. You should use only a little fertilizer about 1 tablespoon per hanging basket.
There are multiple signs of too much fertilizer in the soil. These are a crust of fertilizer on the surface of your soil, yellowing and wilting lower leaves, browning leaf tips and edges leaves falling off, slow to no growth, seedlings don’t grow. You should use a liquid fertilizer with a 2:1:1 ratio of nitrogen, phosphorous, and potassium.
Sources
Mgeldorado.ucanr.edu: The Perils of Over-Fertilizing Plants and Trees
Agrilifeextension.tamu.edu: Fertilizing a Garden
Wikipedia: Nitrogen Fixing Crops
Hortnews.extension.iastate.edu: Care for Blooming Hanging
Fact Checked, Written, and Published by Kevin Rodrigues
Kevin is the founder of Gardening Mentor, a website that aims to teach people to grow their own food in a limited space. As a self-taught gardener, Kevin has spent several years growing plants and creating gardening content on the website. He is certified in Home Horticulture and Organic Gardening from Oregon State University. He has a Post Graduate Diploma in Horticulture and Landscape Gardening from Mumbai University.
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