How To Tell If A HPS Bulb Is Burnt Out

If you want to know how to tell if a HPS bulb is burnt out, there are signs to look out for and expected life spans to consider. Compared to LED bulbs, gardeners know that HPS bulbs often need replacement. However, it cannot be obvious to understand when to replace them, and the last thing you’d want is to replace them too early or too soon. 

We all know how crucial it is to maintain the efficiency of growing light indoors, especially when at the early stages of plant growth. Therefore, greenhouse maintenance doesn’t stop with the usual cleaning and checking of indoor temperature and humidity. It’s also essential for the gardener to know what signs indicate burnt out HPS bulbs and when they’ll need replacement. 


How To Tell If A HPS Bulb Is Burnt Out And What To Expect


Signs to look out for

The most common sign to look for is if the area around the bulbs’ base has turned black. However, this doesn’t mean that you should wait for this physical sign to happen. For example, some gardeners change their HPS bulbs after four or even three harvests based on the fact that HPS bulbs only last 8000 to 16000 hours. 

Therefore, a darkened base’s physical sign may not be present, but the bulbs might already lose lumens. The chance of facing drawbacks in production can occur from this loss, so keep the two tips together in mind. If you notice darkening on the base and it will be your fourth harvest, there’s a good chance the bulb is close to burning out. 

Another telltale sign of burnt-out HPS bulbs is when they flicker a lot or shut off completely. It’s best to replace them because this can lead to a decrease in spectrum color. Remember that spectrum also plays a significant role in the growth lights’ efficiency, so if the bulb looks whiter instead of the usual orange, it’s time to change. 


When to change an HPS bulb

As mentioned earlier, you can wait until the fourth harvest to change an HPS bulb. However, different gardeners also have various founded considerations on when to change the bulb even if it’s not showing signs that it’s burnt out. First, you can replace the bulbs after 18 months, considering that they have a lifespan of 24,000 hours. 

Besides computing how many hours are there in a year, some HPS bulbs will also degrade faster. For example, those with a blue spectrum will also have this spectrum output deteriorate more quickly, making it useless. Instead of 18 months, it’s sensible to replace the HPS bulbs after 10 to 14 months.

The duration of using your bulbs also plays a role in when you should change them. Of course, using the bulbs for 12 to 18 hours a day will burn your HPS bulbs faster. You can even consider how it’s expected for an HPS bulb to last for 20,000 hours, but its intensity tends to lessen after 8,000 hours. 

To prevent problems from insufficient lighting, use a light meter to check the brightness, and consider replacing after the bulb loses 15%. Whether you choose to replace them every 12 or 18 months, ensure that you keep backups in case they burn out earlier. 


How Often Should You Replace An HPS Bulb

Experienced growers replace HPS bulbs every 6 to 10 months if they are under continuous use. Ideally, you want to replace them once a year if you’re using them for 12 hours on and 12 hours off cycle to ensure that their output is still optimal. On the other hand, you can replace HPS bulbs every eight months if they are in 18 hours on and 6 hours off cycle. 

This is why, as mentioned earlier, those who use HPS bulbs with a blue spectrum must replace them quicker because of the degradation of the spectrum itself.  The importance of knowing when an HPS bulb degrades is that it also dictates the potential loss in your yield. To make the explanation more straightforward, a loss of 20% output equates to a loss of 20% yield. 

You might also have to replace earlier if you notice darkening on the ends of the inner arc tube. Not only does this potentially indicate burning out, but the black discoloration will also block the light. Lastly, those who experience power outages should assume a shorter lifespan for their HPS bulb. 


Signs that the HPS bulbs are damaged or used

There will be instances that you feel unsure if the HPS bulbs you have are still new. If you suspect tampering, you can confirm this if there are black specks on the element’s bottom. Shipping can also damage the bulbs and cause scuffing on the base contacts, so always check first before using them. 



Maintaining the greenhouse is vital to ensure that your plants will get their optimal requirements. For lights, are you confident with how to tell if a HPS bulb is burnt out? For starters, you can check some darkening at the base as an indicator. 

Additionally, mark your calendar on when to expect your bulbs to degrade. Even if it isn’t your fourth harvest or it’s earlier than ten months, you may need to replace them, depending on their daily experience. The bottom line here is that you don’t have to wait for the bulbs to burn out, as degradation leads to low output and poor yield. 


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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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