Strawberry plants can do very well in containers if you have limited room in your garden. Like any other fruiting plant, the right fertilizer can help strawberries reach their full potential.
Keeping these plants well-fed in the garden is a cinch. But how do you fertilize strawberry plants that are growing in containers? To solve this conundrum and help my plants flourish, I did some research, which you’ll find below.
How to Fertilize Strawberry Plants in Containers
Fertilization is crucial for any container plant, not just strawberries. Potted plants are unable to spread their roots out like those in the garden.
Plants can use their roots to reach for nutrients when they’re not immediately available. That’s not the case when it’s in a container because they confine the roots. As a result, your plant relies on you fertilizing it to get all the nutrients it needs.
Feeding Your Strawberry Plant
Strawberries usually do not produce quality fruits during their first year. Most of the energy that the plant is using goes to developing the root system and foliage. This is true even in containers.
Your plant may generate runners or small mushy fruit. However, it won’t be until the next growing season until you get harvestable fruits.
Even still, your strawberry plants need fertilizer to continue growing. In the early spring and late fall, strawberries have a higher demand for nitrogen. This is when most plants are producing those runners and small berries.
To support your plant, apply a 10-10-10 fertilizer. You can use a simple powdered or granulated fertilizer product. This form of fertilizer will supplement the soil and give the plant more opportunities to take the nutrients. Granular fertilizers promote even long-term growth.
All fertilizer products are different, so follow the instructions closely. Sprinkle the granules over the soil around the plant. Using your finger or a gardening tool, scratch the granules into the soil a bit.
Then, water the strawberry plant as you normally would. The nutrients will dissolve and mobilize with the water.
When you apply the fertilizer, make sure that you’re not getting any on the stem or foliage. Fertilizers contain salts that could pull moisture out of the plant, resulting in discoloration. Fertilizer burn can kill your plant. Exercise caution and only apply the recommended amount.
When to Fertilize Strawberry Plants
Knowing when to fertilize your plants is just as important as knowing how to get the job done.
With proper care, these plants can continue producing fruit for over five years. But, you must continually provide nutrients throughout the plant’s life. It all starts before you even get the plant in the container.
If you’re using basic potting soil, it’s a good idea to reinvigorate it with nutrients. Old soil can lack the essentials. Plus, its composition could prevent proper drainage and growth.
Before you add your plant, mix the soil up with some slow-release Osmocote fertilizer. This fertilizer looks like granules. However, the tiny particles are prills. They contain a protective coating that slows the release of nutrients in the soil.
Mixing this fertilizer into your soil ensures that your plant can continue to take advantage of it for a few weeks.
One Month After Planting
About a month after your plant settles in, apply another fertilizer. For this application, use a simple 10-10-10 fertilizer in granular form.
This application will help the plant get the required nutrients and promote healthy growth in the container.
From the first year on, you can move to a yearly fertilization cycle. Provide fertilizer every year after the plant has produced fruit. You don’t want to wait too long to fertilize them.
Aim to feed them before September. You can also apply light fertilizer during the spring. But, only do this if the plant is looking worse for wear. You don’t want to overdo it.
The only exception to that rule is June-bearing strawberries. These plants produce a sizable harvest during the late spring and early summer.
If you apply fertilizer in the spring, the plant could develop soft berries. You run the risk of making the plant more vulnerable to diseases as well. It’s best to wait until after the last harvest to apply fertilizer.
Are Coffee Grounds Good for Strawberry Plants?
If you’re a big coffee drinker, you have a great fertilizer right in your coffee pot. Instead of tossing out those coffee grounds, you can use them on your strawberry plants.
I’ve written a post about coffee grounds and where you can get some good quality grounds for free.
Why Are Coffee Grounds a Good Fertilizer?
Coffee grounds are nothing more than spent beans. While you are taking away some of those aromatic compounds when you brew, the beans are still usable in the garden.
That’s because they have a high concentration of nitrogen. They’re about 2 percent nitrogen by volume. Nitrogen is one of the most important nutrients for your garden. Strawberries rely on it to flourish, so why not add some to your container?
Another benefit of coffee grounds is its acidity. Fresh coffee grounds have a lower pH balance, which can raise the acid level of your soil.
It’s important to note that only fresh grounds are acidic. Brewing removes the acidity, so spent grounds are virtually neutral.
Strawberry plants do best in slightly acid soils. They require pH levels between 5.5 and 6.9. There are several ways to get the pH balance just right in your soil. But, using coffee grounds is one of the easiest and most affordable.
So coffee grounds are good for strawberry plants because they provide a good source of nitrogen to it. The slight acidic nature of the brewed coffee grounds helps improve soil acidity. This makes it suitable for strawberry plants that prefer slightly acidic soil to grow well.
How to Use Coffee Grounds
There are a couple of ways to use coffee grounds to your advantage. Before you plant your strawberries, use it to create an acid growing environment by mixing it up with the soil.
Otherwise, you can use old coffee grounds like normal fertilizer. Just sprinkle it over the soil and water your plant. The nitrogen from the coffee grounds will seep into the soil where your plant can take advantage of it.
The third option is to create a “coffee ground tea.” No, this doesn’t mean you should pour straight coffee into your plant.
Instead, let about two cups of used coffee grounds soak in five gallons of water. Let the grounds seep overnight. When you wake up in the morning, you’ll have a nutrient-rich liquid fertilizer.
Use the liquid to water your plants and give them a boost of nitrogen. Do this sparingly whenever your strawberry plant needs a pick-me-up.
Another option you have is to use compost tea. I’ve written a detailed post on how to prepare compost tea that is a cheap fertilizer you can use for your strawberry plants.
Is Miracle-Gro Good for Strawberry Plants?
While many gardeners choose to stick to granulated fertilizer products, Miracle-Gro works well, too.
Water-soluble formula is a good option for June-bearing strawberries. You can also use it for day-neutral or everbearing strawberry plants. However, you’ll need to properly dilute the fertilizer for the latter strawberry varieties.
What is Miracle-Gro?
Miracle-Gro is a brand-name fertilizer that you can easily find on store shelves in your garden center.
The reason gardeners question if Miracle-Gro is a good product for strawberries is its composition. Most of the popular Miracle-Gro products are synthetic fertilizers. This means that they have inorganic compounds.
Many gardeners like to think of fertilizers like Miracle-Gro as plant steroids. They can help give the plant a boost of growth energy. But, they may have negative long-term effects on the soil.
Synthetic fertilizers can kill beneficial microorganisms in the soil. Those microorganisms help convert decaying material into nutrient-rich organic matter.
Some of the ingredients in synthetic fertilizers may have some environmental risks, too. The chemicals wash away into our oceans and rivers, which puts wildlife in danger.
If you do plan on using Miracle-Gro, do so with sparingly. Don’t overdo the application and stick to the instructions on the package.
According to Miracle-Gro, the product is safe for all plants. This includes vegetables, trees, and shrubs. Even still, it’s good to exercise some caution.
Miracle-Gro does have an organic line of fertilizers. These are going to be best for your strawberries. They contain the appropriate nutrients to help your plants flourish without all of the added risks.
Miracle-Gro is good for strawberry plants as long as you follow the instructions while using it in your potting soil. You should pick the organic fertilizer options that are gentle on the soil and won’t harm the beneficial microorganisms.
You should be careful on when you harvest and eat the strawberries from plants where you have used Miracle-Gro.
Are Banana Peels Good for Strawberry Plants?
Old banana peels make a wonderful fertilizer for potted plants including strawberries. The skin of the ever-popular fruit is high in potassium.
The peels also have calcium, magnesium, phosphates, and sulfur. All of those nutrients are beneficial to your strawberry plant, so there’s no reason to throw those peels out.
Benefits of Using Banana Peels
The main nutrient you’re going to be taking advantage of with banana peels is the potassium. Potassium provides a couple of different benefits.
First, the nutrient can help improve Turgor. Turgor is the pressure created by fluids in the plant cell. With more pressure, the plant tissue becomes rigid and strong. The potassium from banana peels can ultimately improve the strength and vitality of your strawberry plants.
Secondly, is capable of helping the plant build up a resistance to disease. Potassium-deficient plants are notorious for succumbing to fungal diseases. With high levels of potassium, the plant has a more efficient barrier against potential pathogens.
Finally, potassium regulates more than 60 enzymes that are responsible for plant growth. The nutrient catalyzes chemical reactions. It’s responsible for regulating photosynthesis, transporting water, and more.
Needless to say, potassium is important. While potash in traditional fertilizers works great, a natural source of the nutrient does the job just the same.
Banana peels are good for strawberry plants because they provide a good source of potassium. This helps improve the resistance of the plant against fungal and bacterial diseases. It also helps improve the plant growth and makes it strong.
How to Fertilize with Banana Peels
There are so many ways to use banana peels. Most will just toss the peel into the compost pile. But, you can also apply it to the plant directly.
For the confined space of a container plant, it’s best to either create a tea or a powder. Banana peel tea is very easy to make. All you have to do is soak several peels in water for a day or two.
The nutrients will release into the water. Like the coffee ground tea from earlier, you can use this solution to water your plants.
To create a powder, you’ll need to dry out your banana leaves first. You can do this in the oven for quick results. Or, you can leave the peels out in the sun to dry naturally.
Once they’re nice and crispy, grind the peels up into a fine powder. Then, sprinkle it over the soil.
Banana peels are one of the 27 natural fertilizers that you can use for free or cheap for your strawberry plants.
Is Epsom Salt Good for Strawberry Plants?
You might have some experience using Epsom salt to treat stress and bodily pains. But, the unique mineral compound has a place in the garden, too.
Epsom salt is a water-soluble compound of magnesium sulfate. It contains both magnesium and sulfur, which are great for strawberry plants.
Benefits of Using Epsom Salt
Epsom salt can improve the growth of flowering and fruiting plants.
The magnesium in Epsom salt enhances the plant’s ability to take in valuable nutrients. It’s also capable of helping the plant create chlorophyll. As a result, your strawberry plant will look greener and much healthier.
Unlike most commercial fertilizers, Epsom salt won’t build up over time. With other fertilizers, it’s easy to overdo things and accidentally ruin the quality of the soil. That’s not the case with the Epsom salt, so there’s virtually no risk in using it.
Epsom salt is good for strawberry plants because it helps the plant create more food. This improves the growth of the plant and keeps them healthy.
How to Use Epsom Salt on Strawberry Plant
The best way to take advantage of the magnesium in Epsom salt is to dilute it in water.
Add about a tablespoon of Epsom salts to a gallon of water. Let the solids dissolve completely and water your plants as normal. You can use the dissolved salts to feed your plants after flowering and fruit set. This should help to develop larger berries.
Epsom salt may also help deter pests. If you’re dealing with garden pests like snails and slugs, sprinkle some salts around the base of the plants. This can create an effective barrier that keeps them away.
How Do I Get My Strawberries to Grow Bigger?
Every gardener wants to enjoy large crops. While many believe that you can’t achieve sizable harvests with container plants, that’s simply not true.
Here are some steps you can take to get the biggest strawberries possible.
Fertilize at the Right Time
Fertilizing at the right time is key. Generally, it’s best to fertilize in the spring after new growth begins and after the plant stops producing for the season.
There are some exceptions. Refer to the section above to get more information about when to fertilize your strawberries.
Ultimately, the goal is to keep the plant healthy all year long. Even when it’s not producing fruit, you must keep the plant flourishing. This will give it the energy it needs to create huge berries.
Don’t Harvest During the First Year
In the first year, your plant is not going to grow any usable fruits. If it does manage to fruit a bit, the berries are going to be mushy and unpalatable.
It’s best to pick off blossoms during the first year. This discourages the plant from fruiting, allowing it to focus its energy on developing better roots. This results in an impressive harvest during the second year.
Runners are going to divert valuable energy away from the plant. The plant develops runners early in the season. They look like horizontal roots.
If you let the runners continue growing, they’ll take root and develop a clone plant. That’s not where the plant’s energy needs to go. So, prune them off.
Pruning the runners will result in a smaller yield. But, the berries you do harvest will be bigger.
Pick Ripe Berries When They’re Ready
When your strawberries are ready for picking, don’t hesitate. The plant will continue to support the berry if you leave it on. That’s a waste of energy.
Picking ripe fruits allow the plant to focus on making smaller underdeveloped berries bigger.
Replace the Plant
Strawberry plants can produce fruit for several years. But, that doesn’t mean that the fruits will continue to be big.
After about three years, most plants will weaken. Moving forward, your berries will likely be smaller. Plus, plants older than three years tend to be more susceptible to disease.
If you want to continue harvesting large strawberries, you’ll need to replace the plant. You can start a new plant or transplant runners to get a clone of the original.
What is the Best Fertilizer for Strawberries?
Strawberry plants respond well to a wide range of fertilizers. As long as they’re getting the nutrients they need, the plants aren’t picky. Here are some good fertilizer options to help your strawberries reach their full potential.
Balanced Commercial Fertilizers
Commercial fertilizer products contain a blend of nutrients that your plant will take advantage of.
It’s best to stick to balanced fertilizers than have an even ratio of nitrogen, phosphorus, and potassium. The numbers on fertilizer products reflect the blend, so it’s easy to choose an appropriate one.
A good universal choice is a simple 10-10-10. It’s safe, effective, and easy to apply. Whether you choose a granular formula or a water-soluble one, your plant will flourish.
These types of fertilizers are completely organic. Usually, they contain high levels of nitrogen, which are great for strawberries. You can use cow manure, bone meal, fish products, and more.
Nothing beats natural compost. Compost is a simple organic matter that results from natural decomposition. You can create compost out of pretty much everything.
Natural food byproducts, such as the banana peels and coffee grounds we went over earlier, are perfect for compost. The same goes for yard debris, leftover vegetables, and anything else that breaks down.
After the organic matter transforms into compost, use it to enrich the soil. Your strawberry plants will leach the nutrients from the compost to grow strong.
The store-bought compost can be expensive and it may not contain all the required nutrients. You can make your own compost to save money and ensure the right materials are used for the best quality.
Here are some of my favorite container gardening tools
Thank you for reading this post. I hope it helps you with your gardening needs. I’ve listed some tools below that can help you with container gardening. These are affiliate links so I’ll earn a commission if you use them.
Gardening Gloves – I find the Pine Tree Tools Bamboo Gardening Gloves really good for both men and women. It’s made from bamboo so helps absorb perspiration. They are also comfortable and fit very well.
Containers – You know picking the right container is crucial for your container gardening. I’ve written a detailed post on the best containers you can choose from. If you’re happy with a plastic container, you can check out the Bloem Saturn Planter.
Watering Can – This is a must-have tool when you’re growing plants in pots or grow bags. It helps to water the potting soil without splashing on the foliage. The Kensington Watering Can is stylish, strong, and can provide precision when watering potted plants.
Trowel – Garden Guru Trowel is my favorite because it’s durable and comfortable to use. My gardening friends really love having a trowel because they use it for digging soil, mixing fertilizer, moving seeds, leveling out the soil, mixing compost or mulch, and also dividing tubers
Bypass Pruner – I really like the Corona Bypass Pruner because it’s durable and gives a clean cut that helps plants recover faster. If you’re looking for something cheap, get the Fiskars Bypass Pruner that is really good as well.
To see an extensive list of the best container gardening tools gardeners recommend, check out this resource that I made for you.
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 by expert gardeners from Oregon State University.