Do you love growing plants? Do you want to grow them in pots? Plants in pots need extra help. That’s where fertilizer for container gardening comes in! It gives your plants the food they need. Let’s learn all about it.
Imagine a tiny plant in a pot. It has roots that can’t reach far. It needs fertilizer for container gardening to grow big and strong. It’s like giving your plant a healthy snack.
Why is fertilizer for container gardening important? It helps plants grow. It makes them healthy. It helps them produce flowers or fruits. Without it, your plants might not do so well.

Key Takeaways
- Fertilizer for container gardening gives plants the nutrients they need to thrive.
- Choose the right type of fertilizer based on your plants’ specific needs.
- Always follow the instructions on the fertilizer package carefully.
- Organic fertilizers are a great option for healthy and sustainable gardening.
- Regularly fertilize your container plants to keep them growing strong all season.

Why Use Fertilizer for Container Plants?
Plants in containers need our help. Unlike plants in the ground, they can’t reach for nutrients. Their roots are stuck in a small space. The soil in containers loses nutrients over time. Watering washes away important stuff. Fertilizer for container gardening replaces these lost nutrients. It is like giving your plants a vitamin boost. Without it, plants can get weak. They might not grow well or produce flowers. They may get sick and die. Using fertilizer helps them stay strong and healthy. It keeps them growing all season long. You will see bigger, better plants with lots of blooms or tasty vegetables. It makes your container garden a success.
- Container plants can’t get nutrients from the ground.
- Watering washes away nutrients.
- Fertilizer replaces lost nutrients.
- It helps plants grow strong.
- Healthy plants produce more flowers or fruits.
Think of fertilizer as food for your plants. Just like you need to eat healthy food to grow, plants need nutrients. These nutrients help them make food through photosynthesis. Fertilizer contains essential elements like nitrogen, phosphorus, and potassium. Nitrogen helps with leafy growth. Phosphorus helps with roots and flowers. Potassium helps with overall plant health. When you use fertilizer for container gardening, you are giving your plants the ingredients they need to thrive. It is like baking a cake. You need flour, sugar, and eggs. Plants need nitrogen, phosphorus, and potassium. Fertilizer provides these ingredients, ensuring your plants grow big and strong.
What Nutrients Do Plants Need?
Have you ever wondered what plants eat? They don’t eat pizza or ice cream. Plants need special nutrients to grow. These nutrients are like vitamins for plants. The most important ones are nitrogen, phosphorus, and potassium. Nitrogen helps plants grow big and green leaves. Phosphorus helps them make strong roots and beautiful flowers. Potassium helps them stay healthy and fight off diseases. When you use fertilizer for container gardening, you are giving your plants these important nutrients. It’s like giving them a balanced meal. Without these nutrients, plants can get sick and weak. They might not grow as tall or produce as many flowers. So, remember to feed your plants with the right nutrients to keep them happy and healthy.
Why Is Container Soil Different?
Imagine you have a garden in the ground. The soil is full of nutrients. The roots can grow deep to find them. Now, imagine a plant in a container. The soil is limited. The roots can’t reach far. Container soil is different. It drains faster. Nutrients wash away more easily. This means plants in containers need extra help. They need fertilizer for container gardening. The fertilizer adds back the nutrients that are lost. It helps the plants grow strong and healthy. Think of it like this: ground soil is like a buffet with lots of food. Container soil is like a small plate. You need to refill the plate with fertilizer so the plant gets enough to eat.
How Does Fertilizer Help Plants Grow?
Have you ever seen a plant that looks sad and droopy? It might need fertilizer! Fertilizer helps plants grow in many ways. It gives them the nutrients they need to make food. Plants make their own food using sunlight, water, and air. But they also need nutrients from the soil. These nutrients help them grow strong stems, big leaves, and beautiful flowers. Fertilizer for container gardening provides these nutrients. It’s like giving your plants a boost of energy. When plants get enough fertilizer, they grow faster and healthier. They can fight off diseases and pests. They produce more flowers and fruits. So, if you want your plants to thrive, remember to give them fertilizer.
Fun Fact or Stat: Did you know that plants use sunlight, water, air and fertilizer to create their own food through a process called photosynthesis?

Types of Fertilizer for Potted Plants
There are many kinds of fertilizer for container gardening. It can be confusing to choose! Some fertilizers are made from chemicals. These are called synthetic fertilizers. They work quickly. Other fertilizers are made from natural materials. These are called organic fertilizers. They release nutrients slowly. Some fertilizers come in liquid form. You mix them with water. Others come in granules or sticks. You sprinkle them on the soil. The best type depends on your plants. It also depends on what you want. Some people like the quick results of synthetic fertilizers. Others prefer the natural approach of organic fertilizers. Read the labels carefully. Choose the right fertilizer for your plants and your gardening style.
- Synthetic fertilizers work quickly.
- Organic fertilizers release slowly.
- Liquid fertilizers mix with water.
- Granular fertilizers sprinkle on soil.
- Choose the best type for your plants.
Choosing the right type of fertilizer is important. Synthetic fertilizers are like fast food for plants. They give a quick boost but don’t always provide long-term benefits. Organic fertilizers are like a healthy, home-cooked meal. They nourish the soil and the plants over time. Liquid fertilizers are easy to apply. They are good for plants that need a quick fix. Granular fertilizers release slowly. They are good for plants that need a steady supply of nutrients. Consider what kind of plants you have. Some plants, like tomatoes, need a lot of nutrients. Others, like succulents, need very little. Research your plants and choose the fertilizer that best suits their needs. Using the right fertilizer for container gardening will help your plants thrive.
What Is Slow-Release Fertilizer?
Imagine a candy that slowly melts in your mouth. It gives you a taste of sweetness for a long time. Slow-release fertilizer is like that candy for plants. It slowly releases nutrients into the soil. This means your plants get a steady supply of food over time. You don’t have to fertilize as often. This is very convenient. Slow-release fertilizer is great for container plants. They need a consistent source of nutrients. It prevents them from getting too much fertilizer at once. Too much fertilizer can burn their roots. Fertilizer for container gardening that is slow-release is a good choice for busy gardeners. It is also good for beginners. It makes fertilizing easier and more effective.
What Is Liquid Fertilizer?
Have you ever taken a vitamin drink? It’s a quick way to get the nutrients you need. Liquid fertilizer is like a vitamin drink for plants. It’s a concentrated liquid that you mix with water. Then, you pour it onto the soil. The plants absorb the nutrients quickly. Liquid fertilizer is great for plants that need a boost. It is also good for plants that are not growing well. You can use it to give them a quick pick-me-up. Fertilizer for container gardening that is liquid is easy to use. Just follow the instructions on the bottle. Be careful not to use too much. Too much liquid fertilizer can burn the plants. It is best to use it sparingly and regularly.
What Is Organic Fertilizer?
Think about eating organic food. It’s grown without harmful chemicals. Organic fertilizer is the same idea for plants. It’s made from natural materials. These materials include compost, manure, and bone meal. Organic fertilizer is good for the environment. It helps improve the soil. It releases nutrients slowly, which is good for plants. It doesn’t burn the roots like some chemical fertilizers can. Fertilizer for container gardening that is organic is a great choice for gardeners. It is good for the plants and the planet. It helps create a healthy and sustainable garden. Plus, it’s safe to use around kids and pets.
Fun Fact or Stat: Organic fertilizers not only feed your plants but also improve the soil structure, making it better for future growth!

How to Choose the Right Fertilizer
Choosing the right fertilizer for container gardening can seem hard. But it’s not! First, know your plants. What kind are they? Some plants need more nitrogen. Others need more phosphorus. Look at the fertilizer label. It has three numbers. These numbers show the percentage of nitrogen, phosphorus, and potassium (N-P-K). For example, a 10-10-10 fertilizer has equal amounts of each. A 20-10-5 fertilizer has more nitrogen. Choose a fertilizer that matches your plants’ needs. Also, consider the type of fertilizer. Do you want synthetic or organic? Liquid or granular? Think about what is easiest for you to use. Read reviews and ask other gardeners for advice. With a little research, you can find the perfect fertilizer for your container garden.
- Know your plants’ needs.
- Check the N-P-K numbers.
- Choose synthetic or organic.
- Consider liquid or granular.
- Read reviews and ask for advice.
The N-P-K ratio is important. It tells you the amount of nitrogen, phosphorus, and potassium in the fertilizer. Nitrogen helps with leafy growth. Phosphorus helps with root development and flowering. Potassium helps with overall plant health. If you want your plants to have lots of green leaves, choose a fertilizer with a higher nitrogen number. If you want them to produce lots of flowers, choose one with a higher phosphorus number. If you want them to be strong and healthy, choose one with a higher potassium number. Many fertilizer for container gardening options have a balanced N-P-K ratio. This is a good choice for general use. However, if you have specific needs, choose a fertilizer that targets those needs.
What Does N-P-K Mean?
Have you ever seen three numbers on a fertilizer label? These numbers are called N-P-K. They stand for nitrogen, phosphorus, and potassium. These are the three most important nutrients for plants. Nitrogen helps plants grow big, green leaves. Think of it like a building block for the plant’s body. Phosphorus helps plants grow strong roots and beautiful flowers. It’s like the plant’s energy source. Potassium helps plants stay healthy and fight off diseases. It is like the plant’s immune system. When you choose fertilizer for container gardening, look at the N-P-K numbers. They will tell you what kind of nutrients the fertilizer contains. Choose one that matches what your plants need.
Do Different Plants Need Different Fertilizer?
Imagine you have a dog and a cat. They both need food, but they eat different things. Plants are the same way. Different plants need different fertilizers. Some plants, like tomatoes, need a lot of nitrogen to grow big and strong. Others, like succulents, need very little fertilizer. They can be harmed by too much. Flowering plants need more phosphorus to produce lots of blooms. Leafy greens need more nitrogen to grow big leaves. Fertilizer for container gardening should be chosen based on the plants. Do some research to find out what your plants need. Then, choose a fertilizer that provides those nutrients. It will help your plants thrive.
How Do I Read Fertilizer Labels?
Reading fertilizer labels can seem tricky, but it’s not too hard. The most important thing to look for is the N-P-K ratio. This tells you the amount of nitrogen, phosphorus, and potassium in the fertilizer. The numbers are always in the same order: N-P-K. So, a fertilizer labeled 10-20-10 has 10% nitrogen, 20% phosphorus, and 10% potassium. The label also tells you how to use the fertilizer. It will say how much to use and how often to apply it. Always follow the instructions carefully. Using too much fertilizer for container gardening can harm your plants. It is always better to use less than more. The label may also list other nutrients. These can include iron, calcium, and magnesium. These nutrients are also important for plant health.
Fun Fact or Stat: The numbers on fertilizer labels (N-P-K) represent the percentage of each nutrient by weight!

How to Apply Fertilizer Correctly
Applying fertilizer for container gardening correctly is important. You don’t want to hurt your plants! First, read the instructions. They will tell you how much fertilizer to use. They will also tell you how often to apply it. For liquid fertilizer, mix it with water. Then, pour it onto the soil. For granular fertilizer, sprinkle it around the base of the plant. Be careful not to get it on the leaves. Water the fertilizer into the soil. This helps it reach the roots. Don’t over-fertilize. Too much fertilizer can burn the roots. It can also pollute the environment. Fertilize regularly during the growing season. This is when plants need the most nutrients. With the right technique, your plants will thrive.
- Read the instructions carefully.
- Mix liquid fertilizer with water.
- Sprinkle granular fertilizer around the base.
- Water the fertilizer into the soil.
- Don’t over-fertilize.
Timing is key when applying fertilizer. Fertilize during the growing season. This is usually spring and summer. Plants need more nutrients when they are actively growing. Don’t fertilize in the winter. Plants are dormant then. They don’t need as much food. Apply fertilizer in the morning or evening. Avoid fertilizing in the heat of the day. The fertilizer can burn the plants in the hot sun. Water your plants before fertilizing. This helps the fertilizer spread evenly. It also prevents the fertilizer from burning the roots. When using fertilizer for container gardening, be consistent. Fertilize regularly, following the instructions on the label. This will help your plants stay healthy and strong all season long.
How Often Should I Fertilize?
Imagine you are eating a meal. You don’t want to eat too much at once. You also don’t want to go too long without eating. Plants are the same way with fertilizer. They need regular feedings, but not too much at once. How often you should fertilize depends on the type of fertilizer you use. Slow-release fertilizers only need to be applied once or twice a season. Liquid fertilizers need to be applied more often, usually every two to four weeks. Check the instructions on the fertilizer label. They will tell you how often to fertilize. Also, watch your plants. If they look pale or weak, they might need more fertilizer. If they look burnt or brown, you might be using too much. Fertilizer for container gardening should be applied at the right frequency for best results.
What Happens If I Use Too Much Fertilizer?
Have you ever eaten too much candy? You might get a stomachache! Plants can also get sick if they get too much fertilizer. Using too much fertilizer can burn the plants’ roots. This is because the fertilizer contains salts. These salts can draw water away from the roots. This can cause the plants to dry out and die. Too much fertilizer for container gardening can also lead to leaf burn. The leaves might turn brown and crispy. The plants might also grow too fast, making them weak and leggy. If you think you have used too much fertilizer, flush the soil with water. This will help remove the excess fertilizer. Be careful not to over-fertilize your plants.
How Do I Water After Fertilizing?
Imagine you are taking a shower. You need to rinse off the soap to get clean. Plants need to be watered after fertilizing to help the fertilizer reach the roots. Watering also helps prevent the fertilizer from burning the leaves. After you apply fertilizer for container gardening, water the plants thoroughly. Water until the water drains out of the bottom of the pot. This ensures that the fertilizer is evenly distributed throughout the soil. Be careful not to over-water. Over-watering can lead to root rot. Water the plants gently. Avoid splashing water on the leaves. This can spread diseases. Watering after fertilizing is an important step in keeping your plants healthy.
Fun Fact or Stat: Watering after fertilizing helps prevent fertilizer burn and ensures even distribution of nutrients in the soil!
DIY Fertilizer Options for Containers
You can make your own fertilizer for container gardening! It’s fun and easy. Plus, it saves money. One option is compost tea. Soak compost in water. Then, strain the liquid. Use it to water your plants. Another option is banana peel fertilizer. Bury banana peels in the soil. They release potassium as they break down. Eggshells are also good. Crush them and add them to the soil. They provide calcium. Epsom salts can help with magnesium. Mix one teaspoon with water. Then, spray it on the leaves. Coffee grounds are a good source of nitrogen. Sprinkle them around the base of the plants. Making your own fertilizer is a great way to recycle and help your plants grow.
| DIY Fertilizer | Nutrient Provided | How to Use |
|---|---|---|
| Compost Tea | Nitrogen, Phosphorus, Potassium | Soak compost in water, strain, and use the liquid to water plants. |
| Banana Peels | Potassium | Bury banana peels in the soil near the plant’s roots. |
| Eggshells | Calcium | Crush eggshells and sprinkle them around the base of the plants. |
| Epsom Salts | Magnesium | Mix one teaspoon with water and spray on the leaves. |
| Coffee Grounds | Nitrogen | Sprinkle coffee grounds around the base of the plants. |
- Compost tea is a great option.
- Banana peels provide potassium.
- Eggshells add calcium to the soil.
- Epsom salts help with magnesium.
- Coffee grounds are a source of nitrogen.
Making your own fertilizer is not only cost-effective but also environmentally friendly. It reduces waste and helps you control what goes into your plants. Compost tea is a great way to use up old compost. Banana peels are a common kitchen waste that can be turned into a valuable fertilizer. Eggshells can be collected and crushed, providing a slow-release source of calcium. Epsom salts are easily found at most stores. They can help with magnesium deficiency. Coffee grounds are another common waste product that can be used to fertilize plants. When using fertilizer for container gardening made at home, monitor your plants carefully. Look for signs of nutrient deficiency or excess. Adjust your fertilizer recipe as needed. With a little experimentation, you can create a DIY fertilizer that works perfectly for your container garden.
How Do I Make Compost Tea?
Have you ever made tea for yourself? Compost tea is similar, but it’s for plants! It’s a liquid fertilizer made by steeping compost in water. To make compost tea, you need a bucket, water, and compost. Fill the bucket with water. Add a few handfuls of compost. Let it steep for a few days, stirring occasionally. Then, strain the liquid through a cloth or sieve. The liquid is your compost tea! Use it to water your plants. Compost tea is full of nutrients and beneficial microbes. These help plants grow strong and healthy. You can also add other ingredients. These include molasses or fish emulsion. These add extra nutrients. Fertilizer for container gardening made with compost tea is a great natural option.
What Are the Benefits of Using Eggshells?
Imagine you are building a house. You need strong materials like bricks and cement. Plants also need strong materials. One of these is calcium. Eggshells are a great source of calcium for plants. Calcium helps plants build strong cell walls. This makes them more resistant to diseases and pests. To use eggshells as fertilizer, rinse them and let them dry. Then, crush them into small pieces. Sprinkle the crushed eggshells around the base of your plants. You can also add them to your compost pile. They will break down over time and enrich the compost. Fertilizer for container gardening that includes eggshells is a natural and effective way to provide calcium to your plants.
Can I Use Coffee Grounds as Fertilizer?
Do you drink coffee in the morning? Don’t throw away the coffee grounds! They can be used as fertilizer for your plants. Coffee grounds are a good source of nitrogen. They also contain other nutrients like phosphorus and potassium. Nitrogen helps plants grow big, green leaves. To use coffee grounds as fertilizer, let them cool and dry. Then, sprinkle them around the base of your plants. Be careful not to use too much. Coffee grounds are acidic. They can lower the pH of the soil. Some plants like acidic soil. Others don’t. Do some research to see if your plants will benefit from coffee grounds. Fertilizer for container gardening can include coffee grounds for a natural boost of nitrogen.
Fun Fact or Stat: Coffee grounds are acidic, which makes them great for acid-loving plants like blueberries and azaleas!
Troubleshooting Common Fertilizer Problems
Sometimes, things go wrong with fertilizer for container gardening. You might see yellow leaves. This could mean too little or too much fertilizer. Check the soil. Is it dry or soggy? Dry soil means the plant isn’t getting enough nutrients. Soggy soil means the roots are rotting. Adjust your watering and fertilizing schedule. If the leaves are brown and crispy, you might be using too much fertilizer. Flush the soil with water. If the plants are not growing, they might need more fertilizer. Use a balanced fertilizer to give them a boost. Pests can also cause problems. Inspect your plants regularly. Treat any infestations promptly. With a little detective work, you can solve most fertilizer problems.
- Yellow leaves can mean too little or too much.
- Check the soil moisture.
- Brown leaves mean too much fertilizer.
- Slow growth means not enough fertilizer.
- Inspect for pests regularly.
Identifying the problem is the first step. Yellow leaves can be a sign of nutrient deficiency. This could be due to lack of fertilizer or poor soil. It can also be caused by over-watering. Brown leaves are often a sign of fertilizer burn. This is caused by using too much fertilizer. Slow growth can be caused by a lack of nutrients or sunlight. Pests can also stunt plant growth. Inspect your plants carefully for signs of insects or diseases. Once you identify the problem, you can take steps to fix it. Adjust your watering and fertilizing schedule. Use the right type of fertilizer for container gardening. Treat any pest infestations. With a little care, you can keep your plants healthy and thriving.
Why Are My Plant’s Leaves Turning Yellow?
Imagine you are feeling tired and weak. You might be lacking important vitamins. Plants can also show signs of nutrient deficiency. One common sign is yellow leaves. This can be caused by a lack of nitrogen, iron, or other essential nutrients. The yellowing might start on the older leaves or the newer leaves. This can give you a clue about what nutrient is missing. If the older leaves are yellowing, it could be a lack of nitrogen. If the newer leaves are yellowing, it could be a lack of iron. Check the soil pH. High pH can prevent plants from absorbing iron. Use a soil test kit to check the pH. Adjust the soil pH if needed. Fertilizer for container gardening can help correct nutrient deficiencies.
What Does Fertilizer Burn Look Like?
Have you ever gotten a sunburn? Your skin turns red and painful. Plants can also get burned by too much fertilizer. This is called fertilizer burn. Fertilizer burn usually appears as brown, crispy edges on the leaves. The leaves might also turn yellow or drop off. Fertilizer burn is caused by the salts in the fertilizer. These salts draw water away from the roots, causing them to dry out. If you see signs of fertilizer burn, stop fertilizing immediately. Flush the soil with water to remove the excess fertilizer. Prune off any damaged leaves. Be careful not to over-fertilize in the future. Use the right amount of fertilizer for container gardening for your plants.
How Do I Know If My Plant Needs More Fertilizer?
Imagine you are not growing as tall as you should. You might need more food and nutrients. Plants also show signs when they need more fertilizer. One sign is slow growth. The plant might not be getting any bigger. Another sign is pale green or yellow leaves. This indicates a lack of nutrients. The plant might also produce fewer flowers or fruits. If you see these signs, your plant might need more fertilizer. Check the soil pH. Make sure it is in the right range for your plants. Use a balanced fertilizer to give your plants a boost. Follow the instructions on the fertilizer label. Fertilizer for container gardening will help your plants thrive.
Fun Fact or Stat: Yellowing leaves can indicate a nitrogen deficiency, while stunted growth and dark green leaves can suggest a phosphorus deficiency!
Summary
Fertilizer for container gardening is very important for healthy plants. Plants in pots can’t get nutrients from the ground. They need us to give them food. There are many kinds of fertilizer. Some are synthetic, and some are organic. Some are liquid, and some are granular. Choose the right fertilizer for your plants. Look at the N-P-K numbers. Follow the instructions carefully. Don’t use too much fertilizer. You can also make your own fertilizer using compost, banana peels, and eggshells. Watch your plants for signs of problems. With the right fertilizer, your container garden will thrive.
Conclusion
Fertilizer for container gardening is essential for success. It gives plants the nutrients they need to grow big and strong. You learned about different types of fertilizer. You also learned how to apply it correctly. Now, you can create a beautiful and productive container garden. So, go ahead and start planting! With the right fertilizer, your plants will thrive and bring you joy.
Frequently Asked Questions
Question No 1: Why do container plants need fertilizer?
Answer: Container plants need fertilizer because they are growing in a limited amount of soil. The soil in containers loses nutrients over time as plants use them up and watering washes them away. Unlike plants in the ground, container plants can’t reach for nutrients in a wider area. Fertilizer for container gardening replenishes these lost nutrients. It provides the essential elements that plants need to grow strong, healthy, and produce flowers or fruits. Without fertilizer, container plants can become weak, stunted, and less productive. They might even die. Fertilizer helps them thrive in their confined environment.
Question No 2: What are the best types of fertilizer for container gardens?
Answer: The best type of fertilizer for container gardens depends on the plants you are growing and your personal preferences. There are two main categories: synthetic and organic. Synthetic fertilizers are made from chemicals and provide nutrients quickly. Organic fertilizers are made from natural materials and release nutrients slowly. Both types can be effective. Slow-release fertilizers are a good option for container plants. They provide a steady supply of nutrients over time. Liquid fertilizers are easy to apply and can be used to give plants a quick boost. Choose a fertilizer for container gardening that matches your plants’ needs and your gardening style.
Question No 3: How often should I fertilize my container plants?
Answer: How often you should fertilize your container plants depends on the type of fertilizer you are using. Slow-release fertilizers usually need to be applied once or twice a season. Liquid fertilizers need to be applied more often, usually every two to four weeks. Always follow the instructions on the fertilizer label. You can also watch your plants for signs of nutrient deficiency. These signs include yellow leaves, slow growth, and reduced flowering. If you see these signs, your plants might need more fertilizer. Adjust your fertilizing schedule as needed. Remember that fertilizer for container gardening needs to be applied at the right frequency.
Question No 4: Can I use too much fertilizer on my container plants?
Answer: Yes, you can definitely use too much fertilizer on your container plants. Using too much fertilizer can burn the plants’ roots. This is because fertilizer contains salts. These salts can draw water away from the roots. This can cause the plants to dry out and die. Too much fertilizer can also lead to leaf burn. The leaves might turn brown and crispy. If you think you have used too much fertilizer, flush the soil with water. This will help remove the excess fertilizer. Be careful not to over-fertilize your plants. It is always better to use less than more. Monitor your plants after applying fertilizer for container gardening.
Question No 5: What are some signs that my container plants need fertilizer?
Answer: There are several signs that your container plants might need fertilizer. One common sign is yellow leaves. This can indicate a lack of nitrogen or other essential nutrients. Another sign is slow growth. The plant might not be getting any bigger or producing new leaves. Reduced flowering or fruiting can also be a sign of nutrient deficiency. The leaves might also be pale green or have brown edges. If you see any of these signs, your plants might need more fertilizer for container gardening. Check the soil pH and use a balanced fertilizer to give them a boost.
Question No 6: Are there any natural or organic fertilizer options for container plants?
Answer: Yes, there are many natural and organic fertilizer options for container plants. These options are good for the environment and can help improve the soil. Some popular choices include compost tea, banana peels, eggshells, and coffee grounds. Compost tea is made by steeping compost in water. Banana peels provide potassium. Eggshells add calcium to the soil. Coffee grounds are a source of nitrogen. You can also use organic fertilizers that you buy from a store. These fertilizers are made from natural materials and release nutrients slowly. Fertilizer for container gardening can include these natural options.