Using fertilizer to increase farm productivity has been around for thousands of year. Early Romans, Babylonians, Germans, and Egyptians have all been recording utilizing some form of minerals or manure to enhance crop yields. As early as 1620, fish was used as a fertilizer. In the 19th century, guano (or bird droppings) was taken from Peru and Chile to Europe and the US.
Over the years, fertilization materials and methods have changed many times. Advancements in fertilization science have led to higher crop yields, which lets us feed more people. And it has helped develop many of the foods we have available today.
While the indoor gardens we build in our apartments aren’t necessarily curing world hunger, learning how to use fertilizer well can improve your green thumb. This guide aims to help you understand the benefits of fertilizer, how to source it to make your own, and what to look out for when you decide to use it.
What is Fertilizer?
Fertilizer is a chemical or natural substance added to soil or land to increase fertility and increase crop yields. Fertilizer repopulates essential nutrients like nitrogen, potassium, and phosphorous back into the soil. As plants or crops grow, they soak up these nutrients, and then they are lost after the plant is harvested. Also, over time, the soil becomes less nutrient-dense due to runoff from watering, soil erosion, or lack of access to necessary resources.
Fertilizer helps the soil regain its vitality and grow strong and healthy new crops.
Types of Fertilizer
Fertilizer comes in four main types and several different forms. Which type to get and which form ultimately depends on the plants you grow. Let’s take a look at the options for apartment fertilizers.
Organic and Inorganic Fertilizers
Organic fertilizers are made mostly from manure, compost, or animal and plant products. They are a great source of nutrients, but the exact nutrients are often unknown. Inorganic fertilizers are made from chemical components. These could work best if you need a specific nutrient mix to help your plants produce stronger and quicker.
Nitrogen Fertilizers
Nitrogen helps plant growth and is abundant in all fertilizers. As the name states, nitrogen fertilizers focus on providing this specific nutrient above the others.
Phosphate Fertilizers
Plants continuously need phosphorous to help strengthen their root systems and stems. If you notice your plants have stunted, adding extra phosphorous could encourage more growth.
Potassium Fertilizers
Potassium helps plants grow deeper and stronger roots. It can also help protect your plants from a lack of other nutrients and diseases that may infect your garden. Signs of potassium deficiency include yellowing or browning on the leaves. Potassium fertilizer should be placed as close to the roots as possible.
Forms of Fertilizers
Fertilizer today comes in multiple forms. Some forms are better for releasing nutrients quickly, while others focus on a steady, slower release time.
Liquid Fertilizers
Liquid fertilizers provide a steady supply of nutrients that can be precisely controlled by the home gardener. Liquid fertilizers are diluted into water and applied with a watering can. Some suggest fertilizing your plant every time you water and some every other time. Ultimately, it depends on the type of plant and how often it should be fed.
Release Fertilizers
These have become increasingly popular for both indoor and outdoor gardening. Slow-release fertilizers have a time-release shell that slowly leaches the nutrients into the soil. This provides staggered feeding over time. Single applications can last for months. Typically, these cost more to purchase up front, but the cost evens out over time.
Granular Fertilizers
Dry pellets or pure fertilizer can be mixed directly into the potting soil. This is more common in outdoor gardens than inside ones. Granular fertilizers can be tricky because they dump all of the nutrients at once when the plant is watered. This makes it difficult to control, and the fertilizer can wash out of the pot quickly.
Compost VS Fertilizer
Compost is a mixture of decomposed organic matter, typically plant and food waste or manure. Fertilizers, on the other hand, can be organic or synthetic. Many gardeners don’t choose one but use both to feed their gardens. When using fertilizer, you can determine the exact chemical makeup and satisfy your garden’s needs based on soil tests. Compost is less precise but still provides essential nutrients for the soil. Compost is also an attractive option to gardeners because of its organic nature and how inexpensive it is to produce.
When choosing between compost and fertilizer, let the needs of your plants help you determine which is best by performing soil tests before application.
Nutrients for Plants
Nitrogen, phosphorus, and potassium are natural chemical elements and serve as macronutrients for plant health and growth.
Nitrogen (N) encourages healthy foliage growth. It’s the most abundant element in Earth’s atmosphere.
Phosphorus (P) encourages plants to have a bigger, healthier bloom. It’s a mineral found in bones and in the 1840s was also discovered in bird and bat guano.
Potassium (K) encourages strong roots in plants. In bodies, potassium is commonly used to help bodies work properly and is essential for tissue health.
Besides macronutrients, fertilizers also provide essential micronutrients like magnesium, manganese, and boron.
When To Use Fertilizer
For indoor plants, fertilizers are great to boost a plant’s growth and health. However, timing your applications are important. Using fertilizer on indoor plants should happen when they are actively growing. Feeding them while dormant can kill the plants. It’s also important to not apply too much fertilizer. In fact, it’s considered better to provide not enough fertilizer than too much.
Typically, you can find details of feeding and fertilization on your plant guides. It’s always best to consider the plant’s actual needs rather than apply broad strokes of fertilizer usage.
One way to understand your plant’s needs might be to perform a soil test. You can purchase soil tests from nurseries or home improvement stores. There are also several different DIY tests you can perform.
How to Make Your Own Fertilizer and Compost
Banana Peels
Peels provide a rich source of potassium and small amounts of nitrogen, phosphorus, and magnesium. They are an ideal slow-release fertilizer since they break down over time.
Eggshells
Eggshells offer a rich source of calcium and help reduce acidity in the soil. They also contain phosphorus and other beneficial minerals. You can crush the eggshells and mix them into your potting soil or soak them in water, then use the mix to water your plants. Be sure to wash and remove the inner membrane of the eggshells before using them.
Worm Tea
Worm farms can turn kitchen scraps into food for your plants. By placing your fruit and vegetable scraps on the top of a worm farm, they will be naturally broken down to create a liquid tea you can put on your plants.
Cooking Water
Steaming and boiling vegetables produce water full of nutrients that can benefit plants. After you’ve finished cooking, allow the water to cool before using it for your plants.
Coffee Grounds
Mix a scoop of used coffee grounds into your potting mix before planting to make the soil more acidic.
Green Tea
Used tea bags can make quality and inexpensive houseplant food. Empty the tea leaves from the bag onto the soil around the plant. Similar to coffee, it helps create more acidity.
Epsom Salt
Dissolving a teaspoon of Epsom salts into about a quart or liter of water can create fertilizer that’s high in magnesium and sulfate.
Fish Tank Water
After cleaning a fish tank, you can use the water, which contains abundant nutrients like nitrogen and potassium from the fish waste, to water your plants and fertilize your soil.
Hair
Hair trimmings from humans and animals will break down and provide nitrogen and magnesium.
Molasses
One tablespoon of molasses mixed with half a gallon of water provides a nutritious drink for your plants.
Compost Bins
Compost bins come in several shapes and sizes, and methods may vary. But, the basic principle is to collect organic waste into a bin or container and let it break down over time. Of course, there are pitfalls to keeping a compost or fertilizer bin in your house, such as the smells or pests they attract. However, there are ways to combat these problems.
There are many things you can put in a compost bin, but here are some of the more common ones for inside bins, broken down into greens and browns.
Greens:
- Fruit and vegetable peels
- Coffee and tea grounds
- Citrus and melon rinds
- Vegetable waste (trimmings or non-edible)
- Houseplant trimmings
- Dead flower heads
- Corn cobs
- Broccoli stalks
- Old herbs and spices
- Eggshells
Browns
- Shredded black and white newspaper
- Shredded printer paper
- Bedding from hamster, rabbits, or guinea pigs
- Fall leaves
- Pinecones
- Nutshells–except walnuts
- Used napkins
- Used paper coffee filters
- Brown paper bags, shredded
Of course there are more, but ultimately it depends on the size of your container and how much compost you want to grow throughout the year. Just keep in mind that items need to be organic and not have any potentially toxic chemicals on them.
Benefits of Making Your Own Plant Food
There are two main benefits of making your own fertilizer. One is sustainability and cost. Instead of purchasing fertilizer, you can use scraps around your house that might otherwise find the trash.
The second main benefit is knowing exactly what’s going into the food for your plants. Since homemade fertilizers and compost are made from organic materials, you don’t have to worry about non-organic chemicals.
Disadvantages
There are a few disadvantages to be aware of with homemade fertilizer. First, storage. Since you are storing it in your home or maybe just outside of it, you’ll need to have a dedicated space that can’t be meddled with or eaten by pets, animals, or children. Compost needs airflow to help things break down and prevent it from smelling too awful. So, most compost containers aren’t airtight and can be easily opened.
The smell is something else to be aware of when developing your own fertilizer. While most organic odors will dissipate within a few days, you can limit the smell by watering fertilizer into your soil. Each time you water, the organic material washes down and helps eliminate the odor. Placing mulch on top of the fertilizer will also help control the smell and speed up breaking it down.
Perhaps one of the more potentially damaging disadvantages is not knowing exactly what nutrients your compost or fertilizer offers. Again, soil tests will help, but some plants have specific requirements. Be sure that you are providing what the plant needs.
Buying Fertilizer
Making your own fertilizer can be fun, but it does require a bit of planning and preparedness. Of course, you could also purchase a fertilizer either to supplement your supply of homemade fertilizer or to keep your indoor gardening simpler.
When buying fertilizer, you can be confident of its nutrient balance and purchase it in forms that fit your lifestyle. For some, extended-release feeding might make more sense than trying to keep up with it weekly or through constant monitoring.
Also, if you grow fruits or vegetables in your homes, you may need a different feed mix than flowers, vines, or canopies require.
What to Look Out For
Fertilizers can help your plants grow, reduce or prevent diseases in your plants, and help your plants produce more fruit. But, over-fertilization can do more damage than good.
Here are several things over-fertilization can cause and what to look out for:
- Sudden growth up top, but an insufficient root system
- Improper balance of macro- or micronutrients
- Plants can become stressed and weakened, causing disease or wilting
- Lack of pH balance for the needs of the plant
If you start to notice these things, stop fertilizing the plant and test the soil to figure out the root (pun not intended) of the problem. Once you have the information you need, you can begin correcting it.
Fertilizing your indoor plants is a great way to grow a successful apartment garden. By following the above pearls and pitfalls, your plants will be lush and happy throughout the entire year.