For us gardeners, living in a country that has more rainy days than sunny can be a real struggle. For 9 months of the year, it seems the sun never appears. The remaining 3? Well, it’s a little hit and miss! I’ve found it’s the seedlings that struggle the most, as they simply cannot germinate without adequate sunlight.
Luckily, a lack of sunlight no longer poses a problem for many gardeners, and that’s thanks to LED grow lights. These lights are available in a range of sizes, bringing all the benefits of natural sunlight to seedlings and plants at every stage of their development. They are simply hung above your seedlings, switched on and left to work. Many gardeners see results within just a couple of days.
The best grow lights will have the right coverage area and power for your needs. They should also be energy efficient and easy to install. I’ve gone for the reliable and highly effective Garpsen 4 Head Grow Lamp as my top choice. To see how it works, check out the video below:
Most gardeners know the value of a set of grow lights, especially in our ever-disappointing UK climate! But the issue with many grow lights is they offer little versatility. Most grow lights consist of a large rectangular set of lights which needs to be hung at a specific distance from your plants or seedlings.
The Garpsen 4 Head Grow Lamp is a grow light with a difference. Incredibly versatile, this grow light consists of 4 adjustable branches which can be set in any position. Not only does this provide a far larger coverage area, it also allows you to set the lights at varying distances from your plants according to their stage of growth. The lighting modes can be adjusted so that any number of the 4 branches can be switched on individually.
So design-wise, this grow lamp is a real winner. But how about performance? Well, this grow light boasts 3 light modes and 10 dimming levels. The ‘Veg’ or blue light is made up of 28 LED chips, perfect for germination or plants beginning to sprout. The ‘Bloom’ or red light consists of 52 LED chips, suitable for the flowering or fruiting stage. For best results, the blue and red lights can be turned on simultaneously.
Extra features include an adjustable brightness, ranging from 10% to 100% to emulate natural sunlight and support the growth of plants at every stage. Setting up this grow lamp is also very easy. There’s a powerful clip that can be used to attach the light to any surface of up to 2.5” thick.
With a wide illumination area, this grow light is perfect for those with a lot of plants or seedlings to nourish. The flexible branches rotate 360°, and it’s easy to adjust the distance and angle.
Other features include a reliable timer. The lamp can be set to run for 4, 8 or 12 hours at a time. The only downside is you cannot set the lamp to turn on at a specific time, only the amount of time it runs for. However, compared to grow lamps that don’t come with any timer function, this issue is very minor.
Overall, this light is energy efficient. The timer ensures it won’t be switched on for longer than it needs to be, and it doesn’t cost a lot to run. For the innovative design, ease of set up and affordability, this grow lamp remains my top choice!
Unique design allows you to angle and position the lights in any location. Wide coverage area and very versatile
Comes with a 3, 9 and 12 hour timer setting to save energy
Has a combination of lights that can be used depending on the growth of the plant
Very efficient to run so won’t cost you a lot of money
Quiet to run so can be installed in areas used for working and relaxing
Not suitable for those with very little light - more effective if installed on an already bright windowsill or room
Instructions don’t tell you which combination of lights to use for specific purposes so you will need to research this yourself
Cannot set the timer to start at a specific hour when you won’t be there - instead the timer starts when you turn the lights on
For areas that don’t get a lot of light, the Phlizon 1500W Hanging LED Grow Lamp is a great option. This grow light is large and powerful, producing a very bright light across a full colour spectrum.
This grow light has a convenient hanging design and a huge coverage area. It’s suitable for large grow tents, with a range of over 160 x 160cm! It works best when hung at a distance of around 60cm from the plants and seedlings.
One of the most reliable on the market, this grow lamp produces a full spectrum of colour to give your plants and seedlings all they need. It comes with blue, red, IR, UV and white lights to simulate natural sunlight. The blue and red LEDs are essential for plant germination and growth.
This grow light operates at 1500W, while consuming just 200W. The LED chips are high power and long lasting, while they’re also very efficient. The unit is kept cool by 3 fans, although it does still produce a small amount of heat.
In terms of additional features, this lamp is actually very simple. The effectiveness lies in its brightness and large coverage area. Unfortunately, the brightness can’t be adjusted, and these lights cannot be stringed together like others on the market. Each unit needs to be plugged directly into the mains outlet.
As already mentioned, this unit is energy efficient and economical. It’s a great value for money option for gardeners with more plants to tend to, while the included hanging wires and adjustable rope pulley means there’s no separate purchases needed.
Very bright so a good option for darker areas or plants that need a lot of light
Full spectrum design provides plants with all they need for growth
LED lights are high quality and cost-effective
Fans and vents do a good job at keeping the lights cool
Some people found the fans a little noisy
Fan is made from plastic so may not be as durable as other materials like metal
No dimmer function which would be a welcome extra feature
Built using a dual optic lens, this grow light has a fantastic light output. It has a reliable hanging design and a core coverage area of 91 x 91cm. The maximum coverage area is an impressive 121 x 121cm. Weighing just 3.4kgs, it’s very easy to install and hang up.
This grow light produces good results, offering plants all the light they need to flourish. It has a ‘Veg’ switch, consisting of blue and white LEDs. This helps promote plant growth, encouraging healthy germination and seedling. The ‘Bloom’ switch is for flowering and fruiting. This setting utilises red and white LEDs that help plants to flourish. The lights can be used together to meet the requirements of all stages of plant growth.
With powerful fans, this light doesn’t get hot. It runs 70% cooler than HID lights, although some users may find it a little noisy. It’s worth noting that there is no timer function, so this grow light does need to be switched on and off manually.
Compared with other grow lights, this model is very energy efficient. The improved high PAR and lumen output will help maximise your harvest, while each LED has a zener to protect it. If one LED goes out, the others will still work. It consumes just 240W so doesn’t cost a lot to run.
Overall, this grow light is a great value for money option thanks to the wide coverage area and reliable LEDs.
Powerful cooling system means the lights stay cool even when turned on for long periods of time
Good build quality with a durable hanging kit that holds the lights secure
Separate switches for veg and bloom control make these lights very versatile
Works effectively for areas of 91 x 91cm, with a maximum coverage area of 121 x 121cm
Some people found the fans little noisy
Proper eye protection should be purchased separately as the lights are very bright
There is no timer function so this set needs to be switched on and off manually
VIPARSPECTRA Pro Series P1000 LED Grow Light Review
For those with a little more to spend on their grow lights, the VIPARSPECTRA Pro Series P1000 LED Grow Light is worth considering. This grow light has a coverage area of 75 x 75cm, yet it’s the quality and safety that put this grow light up there with the very best.
This grow light boasts a standard hanging design and it’s relatively easy to get set up. Unlike many others on the market, this grow light is fanless. This ensures you won’t be disturbed by noisy fans whilst you’re trying to relax or work. Instead, the solid aluminium heat sinks help dissipate the heat and give the lights a long lifespan.
With a full spectrum of lights, this grow light can be used at every stage of the growth cycle. There’s 600nm of red light, IR, plus 3000K and 5000K of white light spectrum. Your plants will be supported at all stages from veg to flower.
Extra features include a dimmer knob which can be used to tailor the brightness according to what you’re growing. The height of the grow lamp can also be easily adjusted.
One of the key reasons this grow light is worth the extra cost is due to its energy efficiency. It uses SMD LED technology to provide a high PAR output, high energy efficiency and a long lifespan. Your plants will greatly benefit, and your electricity bill won’t skyrocket. It consumes just 100W of power!
While this light does cost more than others on the market, it works extremely well and the height/brightness can be easily adjusted depending on what you’re growing. The fanless design is also a big plus for some users, as it operates far more quietly than other models.
As there are no fans, these grow lights are very quiet
Easy to adjust the brightness using the dimmer function
Produces good results for all stages of growing and cultivation
Easy to install and set up
Wide range of brightness options to use according to the growth stage
Much more expensive than other grow lights on the market with the same coverage area
For those with just a few plants, the Woputne Grow Light Bar is a fantastic option. This 13.2” grow light helps indoor plants maintain their optimal growth status, yet it doesn’t take up a lot of space so can be used in very small areas.
Design-wise, this grow light is extremely convenient. It’s slimline, unobtrusive and easy to set up. Simply stick it to any wall, window or surface using the included sticky tabs. If needed, it can be screwed on for greater security, as it’s worth noting that the sticky tabs do tend to lose their stickiness over time.
Of course, this light lacks the coverage area of other grow lights I’ve mentioned, but for those with just a few plants needing tending to, it’s perfect.
This light is equipped with 48 LED bulbs; 32 red lights and 16 blue lights. The red LEDs contribute to optimal development during a plant’s early life, while the blue LEDs help the plants to grow strong and healthy stems and leaves. Unlike others on the market however, this grow light doesn’t have white light.
For such a small lamp, many people are surprised at the extra features. First of all, this grow lamp has a reliable timer. It can be set to work for either 2 hours, 4 hours or 8 hours at a time. It remembers the setting you chose, repeating everyday so that, once set, there’s no need to worry about turning this lamp on and off again.
Another helpful feature is the dimmable brightness. There’s 4 different brightness settings to choose from, 25%, 50%, 75% and 100%. The brightness can be easily adjusted according to the needs of your plant.
This light is also energy efficient. The LED chips are high efficiency and don’t cost a lot to run, while the integrated timer ensures this lamp won’t be on for a second more than it’s needed!
If you don’t need a massive coverage area and you’re after a high performing yet simple lamp, the Woputne Grow Light Bar is well worth considering.
Produces very good results at every stage of growing and cultivation
Easy to adjust the 4 light levels and colour spectrum
Timer function means you don’t need to manually switch it on and off
Power lead is a good length at 2m
Stickers aren’t the best quality and may weaken over time causing the lights to fall down
Timer function is limited to 8 hours, while others on the market can be set to 12 hours
Gets fairly warm to the touch when left on for long periods of time
The UK isn’t exactly known for being blessed with bright sunlight all year round. In fact, even in the summer it can prove challenging to get enough light to plants.
LED grow lights mimic the sun’s light spectrum, and are therefore an artificial way to deliver ‘sunlight’ to plants. This can help at all stages in the plant’s lifecycle, from germination, to seedling, to bearing fruit.
Choosing the best LED grow light can be a complicated process – there’s a lot of specialist terminology and know-how tied up in the subject.
The following information will clearly explain the basics, to help you on your way!
If you’ve already stepped foot into the wonderful world of LED grow lights, you’ll likely have noticed that there are a lot of abbreviations used. These can be complicated to understand at first, but are useful to have an awareness of.
These are the most commonly found abbreviations, along with what they mean and why they’re relevant.
LED vs. HID
You’re probably already familiar with ‘LED’ (light emitting diode) – in simple terms, these are a type of bulb that emit light. Nowadays, these are often very bright and energy efficient. When presented as grow lights, lots of small LEDs are used to make one grow light. The LEDs are different colours, in order to simulate the full spectrum of light when used altogether.
HID stands for ‘high intensity discharge’. This is used as a broad umbrella term for all gas-discharge lights. The most popular of these lights today, especially for use as grow lights, are metal halide (MH) and high pressure sodium (HPS). MH bulbs can be more useful in the vegetative stage of a plant, whilst HPS are better associated with encouraging flowering.
LEDs for grow lights have become more popular in recent years because they can produce the same light potency as HIDs whilst using less energy. Therefore, they are much more economical to run. Some people find the intensity of HIDs more effective for growing; however, the bulbs can get very hot, which is less of a problem with LEDs.
This abbreviation comes up a lot when looking at grow lights and it may be confusing if you’re unfamiliar with the term. PAR stands for ‘photosynthetically active radiation’; in simple terms this refers to the amount of light that is available to be used for photosynthesis. Different grow lights will produce different levels of PAR. Also, just because the light produces PAR, it doesn’t mean that all of the PAR is produces will be available to the plant. That’s where PPF comes in.
PPF stands for ‘photon synthetic photon flux’. PPF measures how much usable PAR could arrive at the plant from the grow light. This might be improved by lights that are angled in a certain direction. Sometimes, manufacturers will claim a high PAR rating, but it will only be relevant if the plant is directly under that one small area of LEDs. PAR needs to be distributed across the whole light canopy for it to be effective, which can be better measured by PPF.
Different lights are more effective at boosting certain stages of a plant’s growing cycle.
Nowadays, most grow lights have the potential to deliver a ‘full spectrum’ of lights, including IR and UV. This means that they can supply plants with light that has the same qualities as sunlight.
Nevertheless, if you want to make sure that your plant is channelling all of its energy into a certain process – for example growth, or flowering – you may wish to “artificially” influence this yourself. This is where different colours and light settings come in.
Different Light Settings
Not all LED grow lamps have the option to use only some of the lights; however, some of them will make it possible to only use certain colours at a time.
Red light is required for growth at the germination stage (as well as later in a plant’s life). It helps roots to grow and seeds to germinate. There are studies to suggest that blue light could actually impede germination.
Blue lights are responsible for assisting plant growth – helping them grow strong stems and leaves. Therefore, these lights are often used for the vegetative growth stage of a plant.
Red light is also used to encourage plants to flower and produce fruit. For this reason, it is useful later on in the plant’s lifecycle as well. At this stage, often a combination of red and blue lights will be used.
For these reasons, it can be useful when a grow light has settings for illuminating only bulbs of a specific colour. If this is the case, the grow light will usually have two settings, a ‘veg’ setting, and a ‘bloom’ setting. These can be used individually, or together.
Whilst it can be tempting just to assess the wattage of a particular grow lamp, it’s actually more important to be aware of its PAR output.
Wattage refers to the amount of power inputted into the lamp to create a specific brightness, whereas PAR (and PPF) will be a more accurate way to assess how effectively the light will help plants grow.
Many LED grow lights will display to ‘wattage’ ratings – the actual numbers of watts that the light will consume, and the number of watts that would be required to achieve the same brightness if using HID bulbs.
LED lights cost less to run than traditional HID bulbs. They also produce less heat so you will not need to use as much energy cooling the lamp or the space as you would with HID lights.
LED lights can be placed much closer to plants than HID light because they give off less heat. This is a great advantage as it means the lights can be placed closer to the plants and therefore the light can penetrate the canopy of the plants more easily. In addition, it means you don’t need such a tall growing space.
Positioning the LED light the correct distance from your plant wills result in strong healthy crops with no burning or yellowing leaves. When your light is placed too close to the plants you may see bleached or yellow spots on the leaves.
If the LED is too close it can also result in nutrient deficiencies for your plants.
However, it is not always easy to calculate how far away your LED light should be – it’s something that differs depending on the size and power of your lights. It’s best to check the directions that come with your grow light and follow their recommended distances.
However, the following are general distances, to give a broad idea:
For germination: Hang roughly 92 – 100 cm above plants (for approximately 10 hours/day)
For seedlings: Hang roughly 81 – 92 cm above plants (for approximately 12 hours/day)
For plants in vegetative stage: Hang roughly 60 – 80 cm above plants (for approximately 18 hours/day)
For plants in flowering/fruit stage: Hang roughly 45 – 60 cm above plants (for approximately 12 hours/day)
LED Grow Light FAQs
LED lights are much more energy efficient than fluorescent lights, incandescent lights and HID lights. They’re generally safer, cooler, and can be customised depending on your plants’ needs. Using a combination of different LED lights will get the best results.
Blue LEDs will help with photosynthesis – great for younger plants as well. Blue LEDs will especially benefit green leafy plants which don’t bloom.
Green LEDs are great for plants with dense growth – it can get through to the lower layers of foliage.
Red LEDs help encourage flowering and fruiting.
Red light can help during a plant’s germination stage and during flowering. When used during germination, it can help roots to grow and seeds to germinate. Some studies suggest that blue light may even impede germination.
Blue light is responsible for assisting plant growth – helping the plants grow strong stems and leaves. These lights are frequently used during the vegetative growth stage for this reason.
As mentioned, red light is also used to encourage plants to flower and produce fruit. It is useful to use red light later in the plant’s lifecycle, as well as during germination. At this stage, often a combination of red and blue lights will be used.
PAR stands for ‘photosynthetically active radiation’. Simply speaking, this means the amount of light that is available to be used for photosynthesis. However, just because the light produces a certain amount of PAR, it doesn’t mean that all of that PAR is will be available to the plant. That’s where PPF comes in
PPF stands for ‘photon synthetic photon flux’. PPF measures how much usable PAR could arrive at the plant from the grow light. PAR needs to be well distributed across the whole light, not just concentrated in one area, for it to be effective. This can be better measured by PPF.
LED lights will contain some of the correct light waves for growing plants. However, for best results you should use LED lights which have been created purposefully for plants. These will have the correct balance of light colours for growing plants. If they’ve been intended for plants, they will most likely have a cooling system in place to avoid overheating plants. Additionally, LEDs that are specifically intended as grow lights will often have a choice of settings, to allow you to choose which light colour to use at certain parts of the growing process.
Clive Harris is the creator of DIY Garden and a professional landscape gardening consultant with over 6 years experience. In his spare time he enjoys testing the latest gardening equipment and sharing his experiences here on the site. And of course, he absolutely loves his garden and spends many happy hours outside each week growing, mowing, and having fun with his three kids.