How To Fertilize Geraniums Successfully

Taking notes on how to fertilize geraniums is crucial to ensure beautiful booms, so mark your calendar to do it every two weeks in the growing season. Fertilizing geranium will help prevent stunted or yellowing plants, making them one of the annuals that do well with feeding. This is also why working four inches of organic matter into the soil when planting is ideal. 

The University of Massachusetts Amherst even recommends constant fertilization. With these feeding facts and recommendations in mind, you should have thriving and beautiful geraniums either indoors or outdoors. However, you can always play it safe and use the greenhouse if you’re rooting geraniums

Remember that these plants will respond well to these techniques if they are in an ideal environment with their preferred conditions. 


How To Fertilize Geraniums Successfully

How To Fertilize Geraniums: What To Consider



Clemson University recommends fertilizing new flowerbeds and during the growing season. As mentioned earlier, the University of Massachusetts Amherst also said the benefits of constant fertilization. But what are the specific timings for these instances?

You can work the fertilizer in the flowerbeds upon planting or early in spring. And during the growing season, the geraniums will respond well with feeding every two weeks or four to six weeks when they are actively growing. You can also feed outdoor geraniums when your area experiences heavy rains because nitrogen can leach at this condition.

On the contrary, you don’t need to fertilize new indoor geraniums immediately. Instead, feed when they have established themselves and do so every four weeks in spring and summer. You can also fertilize indoor geraniums in the fall and winter every eight weeks, but dormant plants won’t require feeding.

When should you not fertilize geraniums? For starters, be careful not to overfertilize the plants, especially outdoor geraniums. They can cease to bloom, and they might need some time to rest with only water. 


Type of fertilizer

It’s not enough to mark your calendar on the recommended timings for fertilizing geraniums. For example, a typical fertilizer for new flowerbeds is a 10-20-10 fertilizer per 100 square feet. During the growing season, when they’re active, water-soluble fertilizer at half strength should suffice. 

You can then use the same fertilizer for follow-up feedings. Sticking with these recommendations will prevent overfertilizing and problems in nutrients that can negatively affect geraniums. Then, the conditions as the guide on what fertilizer to use to avoid drawbacks. 

For example, nitrogen leaching is expected during the rainy season. With this in mind, you can make sure that you’ll meet the outdoor geraniums’ nitrogen needs by feeding them with a 5-10-5 dry fertilizer. On the other hand, indoor geraniums in pots will have a different fertilizer requirement than those mentioned. 

Potted geraniums use a mix of soil, sand, and peat as a medium, and will need fertilizing once they’re established after two to three months. At this point, you can use two tablespoons of 20-20-20 water-soluble fertilizer to one gallon of water. Speaking of water-soluble fertilizer, this is also the best type for constant feeding of 200 to 250 ppm of nitrogen. 



Once you know the timing and types of fertilizer that work well with geraniums, the proper application will be the last crucial factor to success. For example, constant fertilization prevents nutrient problems, but overfertilization will also cause blooming and growth drawbacks. How does one avoid these problems?

If you’re using a water-soluble fertilizer, you can assume that you need to ensure an adequate amount of water and drainage as well. This way, water can drain through the medium or soil every time you water geraniums and prevent salt buildup. Remember that a medium with high salt content will negatively affect any plant.

You can also prevent this in the greenhouse by using sub-irrigation when you do liquid feeding of 150 to 200 ppm of nitrogen. You can then comfortably monitor the pH and salt levels in the medium. Once the geraniums undergo dormancy in winter, stop feeding to prevent the roots from drying. 

More so, avoid fertilizing outdoor geraniums when it’s scorching since the fertilizer can dry and burn the plants. Lastly, use fertilizer at half the original rate when you make a second application upon planting outdoor geraniums. 


Signs Of Nutrient Deficiencies In Geraniums

The most common symptoms of nitrogen deficiency are delay in growth, stunting, and yellow leaves. This is likely when the gardener doesn’t use a well-decomposed amendment on the soil since it will decay upon application and rob the soil of nitrogen. On the contrary, the plant can have red-purple lower leaves, weak stalks, and stems, leading to necrosis and death if they need potassium. 



Geraniums are one of those plants that respond well to feeding. But to avoid problems in deficiencies and overfeeding, you must know how to fertilize geraniums properly. Start first by learning about the timing, type of fertilizer, and proper application. 

In general, you can work the fertilizer on the soil of outdoor geraniums upon planting. On the other hand, you should only fertilize indoor geraniums once they have established themselves. Afterward, feed every two weeks while the plants are actively growing with a water-soluble fertilizer. 

And while geraniums benefit from constant fertilizing to avoid deficiencies, make sure that you are also watering them adequately. This will drain excess salts and prevent problems in growth later on. 


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How To Prevent Root Rot In Hydroponics: 3 Useful Tips

If you’re a newbie gardener who’s looking to find ways to hone your skills, you’d want to learn how to prevent root rot in hydroponics even before this problem affects your plants.

Hydroponics can be advantageous to crops in more ways than one. However, it also comes with risks of diseases, such as root rot, which can be destructive or even lethal to your plants.

Unfortunately, there are no effective methods to recover the wilted parts that were affected by the root rot once it hits your plants. The only thing you can do if you do not want this catastrophe to befall your crops is to prevent it before it happens. Read on to learn more about this subject.


What is Root Rot?

Root rot is a disease that attacks the plant roots and causes them to suffer decay. This usually happens when a lack of oxygen supply occurs in the substrate.

To give you an idea, think about plant roots that are submerged in water that only has a little oxygen in it. Over time, the plant suffocates and dies.

Aside from rot and decay, this disease also leads to the proliferation of fungi that are naturally present in the soil. These include Rhizoctonia, Alternaria, Pythium, Botrytis, Fusarium, or Phytophthora. As soon as fungi colonies start to grow, they tend to target the weakened roots and infect your precious plant babies.

Once the plant becomes infected, they won’t be able to take in what they need to grow – water, oxygen, and other nutrients. When this happens, it won’t be long before the plant dies.


What is Hydroponics?

In case you’re not aware, the term hydroponic is derived from a Latin word that means “working water”. To put it simply, hydroponics is an art that involves growing various types of plants without soil. If you’re like most people, the first thing that comes to mind when somebody talks about hydroponics would be a picture of plants with roots suspended into the water without using any type of growing medium.


Avoiding Root Rot in Hydroponic Systems

Detecting and identifying root rot can be tricky. When your plants get infected, their leaves and roots gradually wither until the whole crop itself dies from the lack of nutrients, which is a common symptom of many diseases.


What causes root rot in hydroponics?

One of the requirements in hydroponics systems is oxygen. Without it, your plants are basically on the road to death. On the other hand, lack of such is one of the major triggers for root rot, and it must be avoided at all costs.

Just like when planting in soil, you loosen up the ground so that your plants’ roots can have their required intake of oxygen. That is the case for crops grown in aqueous solutions as well. If they cannot breathe, they would not be able to grow.

Another agent for root rot is the temperature. The last thing you would want in your system are parasites that leech nutrients intended for your plants and infect the water during the process. In common terms, these fungi are called molds.

One of the best breeding grounds for these is warm and moist areas. For this reason, if the water temperature inside your reservoir is high, then you are susceptible to it. Something as minor as letting the solutions exposed to sunlight can already be a risk factor.


3 Useful Tips on How to prevent root rot in hydroponics

There is good news! Root rot in hydroponics can be prevented! Just follow these tips:

Tip#1: Use the right air pump

If you do not want root rot to affect your plants, you merely have to avoid its causes. If you need oxygen, keep the water bubbling by providing an air pump of appropriate size, and also give importance to proper ventilation in the room.


Tip #2: Maintain the temperature

The temperature should be maintained within the 70 to 80 degrees F range. Get rid of any materials that can make your system vulnerable to infections, and make sure not to disturb your crops while they are trying to grow.


Tip #3: Get rid of the rotten parts

However, if you failed in preventing the disease, then the rotten parts should be removed immediately. Cut them off as there is no chance of reviving them, and focus on the potential new growth instead. Fix your hydroponics system and eliminate the risks.


Why Give Greenhouse Gardening a Try?

Greenhouse gardening offers numerous benefits to greens aficionados who dare to take their gardening experience to the next level. Aside from acting as a shield against the effects of inclement weather, a mini, hobby, or semi-pro greenhouse can also serve as a protective layer that keeps harmful bugs and critters at bay.

What’s more, its enclosed structure allows you to control your plants’ growing conditions including the temperature, light, moisture, and ventilation of the greenhouse’s internal environment. With a controlled environment, you’ll be able to extend growing seasons and grow plants that aren’t native to your area.



No matter how well-informed you are about how to prevent root rot in hydroponics, you cannot completely eradicate the risks. Therefore, to avoid the worst-case scenario, you should be prepared to sacrifice the infected for the sake of others. While you’re at it, consider trying your hand at greenhouse gardening as well.


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