Choose from a huge range of indoor grow lights, lighting systems, spare bulbs, ballasts and lighting accessories. Matching the right grow light to your intended growing space and environment helps you to maximise the size and quality of your yield. Choose from a selection of low power LED grow lights or traditional HID (HPS/CMH) options.
Read our buyers guide below for help and advice.
Our in-store experts are more than happy to help you by email or call on 0800 085 7995.
Plants require light to photosynthesize, the process that all plants use to convert water, carbon dioxide and nutrients into chemical energy such as sugars and carbohydrates that are stored in the roots and larger leaves. The plant can then use these carbohydrate molecules for its metabolic processes, growth, setting seed, fruit and blossom.
As the seasons change, the colour, intensity and duration of light reaching the surface of our planet shifts. During spring, light intensity and daylight hours slowly increase; the colour of light is high in the blue spectrum. As the year progresses to mid-summer, the intensity of light peaks as does daylight hours. Towards autumn, the daylight hours slowly decreases and the colour of light shifts towards the red-end of the spectrum. The spectrum shift is due to the decreasing angle the light passes through the atmosphere. Plants sense the seasonal changes and prepare change their growing cycle. Annuals cease new foliage production and set flowers for reproduction, continuing their genetic line in the form of seeds. Perennials also cease new foliage production and create hard over-wintering structures such as tubers, bulbs and runners, which are intended to continue growth at the start of the new season.
Indoor growers replicate seasonal cues to promote the type of growth required at a given point in a plant's life cycle. From propagation and vegetative growth through to flowering, using indoor grow lights are essential for replicating the ideal light conditions for the intended stage of growth.
The benefits of indoor plant lighting stem from the high level of control the grower gains over the lighting environment. There’s no need to rely on the British weather for sun – now you can replicate any stage of the growing season for year-round results.
On a hot summer's day, the sun can supply up to 1000 w/m2. This is the highest intensity of light most species of plants can cope with before negative effects start to take hold. Too much intensity can cause the plants to work too hard which could cause adverse effects. Issues such as the tips of plants burning. They struggle to deal with demand, as more water is used than can be transported up the plant. If the light intensity isn’t high enough, the plants growth stunts and the supporting branches can become spindly and weak as they get taller and stretch in an attempt to get closer to the light. Like everything in life, there is a balance.
Choose from our range of grow bulbs with a selection of wattage's and spectral outputs to cater for all sizes of indoor garden.
As a general rule of green thumb, bulb wattage can be used to see how much space a lamp can cover, with a minimum of 30 watts per square foot. Optimal results can be seen at a higher wattage of 50 watts per square foot.
High Intensity Discharge (HID) bulbs, including Metal Halide (MH), High Pressure Sodium (HPS) and dual spectrum are supplied in 250, 400, 600 and 1000 W, with some digital ballasts boosting 1000 W bulbs to 1100 W to maintain light intensity output after the bulb has been used and worn-in.
Fluorescent bulbs are normally lower wattage's when compared with HID bulbs, with Compact Fluorescent Lamps (CFL) shipping in 125, 200, 250 and 300 W. T5 grow lights consume from 48 to 432 W. T5 grow lights are suited to small gardens, such as propagation and vegetative rooms, growing seedlings and micro-greens that require less intense light.
Whilst wattage is not the most accurate measure of intensity of light, it’s an easy way to get a rough idea of the amount of light being produced by a grow light in a given space.
A more accurate measure of light intensity is µmols, which measure the amount of photons emitted by a given light over an area. µmols are often used in more professional, larger scale set-ups using high end equipment. For smaller spaces, wattage is an adequate estimation of lighting requirements in a garden.
Wattages and Footprint
As a general guide:
- A 250 W light can cover an area up to 0.7 m2
- A 400 W light can cover an area up to 0.9 m2
- A 600 W light can cover an area up to 1.2 m2
- A 1000 W light can cover an area up to 1.5 m2
Not all wavelengths of light are able to support photosynthetic processes.
Photosynthetically Active Radiation (PAR) is a measure of the light that the plants can ‘see’ and that is used by the chlorophyll in its metabolic process of photosynthesis. PAR light contains little green light and is heavy in both the red and blue ends of the visible spectrum. Typically, blue light is used for vegetative growth, promoting tight branch spacing while red light is used during bloom and encourages profuse flower sets.
Many species of plants are considered photoperiodic, meaning they require a change in length of ‘night-time’ dark period in order to persuade the plant to progress to the next stage of development. In a natural environment, photoperiodic plants use the diminishing day length as a cue that autumn is approaching so resources should be prioritised to setting flower and fruit to ensure a new generation. When using grow lights, we can manipulate the length of day in order to cause the plants to react how the gardener wants.
In most fruiting species such as tomatoes, cucumbers and peppers, we can keep plants in the vegetative stage until the space has been filled with foliage at which point the daylength is intentionally shortened and the night lengthened to promote flowers to set that will eventually fruit. This technique ensures the plants will have filled out the garden, making use of all available light; so you get the largest yield out of your space.
Inverse Square Law
The relationship between the intensity of the grow light and the distance from the plants is described as the inverse square law. This means that the further away from the light source your plants are, the less light they receive. For every doubling of distance away from the light source, the intensity of the light will quarter. for this reason it’s important to get your grow lights as close to the top of the canopy as possible. The inverse square law also works for infrared radiation so the heat from the grow bulbs will also increase as the light intensity does.
If you place your hand underneath your light at the height of your plants, you should get a feel for how much infrared radiation (heat) they are receiving. You should try and get your grow lamps as close to the canopy as possible while keeping the temperature at canopy level comfortable. If your hand at the level of the canopy gets too hot, you’ll need to increase the height of the grow lights.
Cost of Running Grow Lights
The cost of running grow lights will depend on your cost of electricity (measured in pence per kilowatt hour), the total wattage of your lights and the amount of time per day they are on for.
As an example, a 600 W light running 12 hours a day with 15p/kWh costs.
First convert the total wattage of the lights from watts to kilowatts. There are 1000 W in a kilowatt, so divide the total wattage by 1000.
600 W = 0.6 kW
Multiply the kilowatts of the lights with the hours in a day they’re on for to get the kW usage per day, in this example, we'll use a normal 12 hr flower regime.
0.6 kW x 12 hrs = 7.2 kWh
Times the kWh per day with the cost of your electricity per kWh to obtain the price in pence to run your lights for 12 hours in a 24 hour period.
7.2 kWh x 15 = 108p = £1.08
You can then multiply this by the number of days your crop will take, for a typical 60 day flowering period, you multiply the cost of running the lights for a day by the number of days.
£1.08 per day x 60 days = £64.80
For a more accurate measurement, most grows require you to work out a two-level cost as the lights are on for longer, usually 18 hours in a 24 hour period when the plants are in the vegetative stage.
Types of Grow Light
High Intensity Discharge (HID)
High intensity discharge grow lights produce light by passing an electric arc through an inert gas. They are highly efficient, producing a higher amount of PAR light than fluorescent and incandescent bulbs. The type of metal salt included in the fitting denotes the spectrum produced.
MH lights use a variety of metal halides to produce the desired spectral output. For horticultural uses, these lights lean heavily on the blue end of the spectrum, which is perfect for promoting vegetative growth.
HPS bulbs contain a sodium vapour that emits light towards the red end of the spectrum. Orange and reds replicate the colour of the autumn sun and so are perfect for flowering.
dual spectrum grow lights
Dual spectrum grow lights are based on the anatomy of an HPS grow light, with the inclusion of metallic salts. The salts provide the ability for the bulbs to emit light from both the red and blue spectrum. This means HPS dual spectrum bulbs can be used for both vegetative and flowering stages of your plants growth.
Ceramic metal halides are the most recent addition to the high intensity discharge market. They offer many of the benefits of HID with few of the draw backs. They offer a full spectrum similar to the sun and run cooler. CDM bulbs are extremely efficient and two 315 W CDM units can perform as well as 1000 W HPS.
Eco bulbs – Energy saving grow lighting
CFL’s have a low power consumption and light output. They’re perfect for confined spaces as a veg cycle light. CFLs specifically for flowering (high in red) are available, but you’ll typically get better results using an HID light.
Using a similar technology to CFL’s, T5 Grow lights are often used for propagation and veg. HID’s are generally used for flower due to better results, but red bulbs exist for the growers who wish to flower under T5’s.
The use of LED grow lights was pioneered by NASA for the growth of leafy edibles on the international space station, mainly due to their potential for low power use. The spectrum of an LED panel can be specifically tailored.
The research into the best combination of colours is ongoing, but LED grow units utilise PAR light by using mostly red and blue LED’s; the colours most associated with photosynthesis. LED grow lights don’t require a ballast and the individual LED’s already angle the produced light downward so there's no need for reflectors. The initial cost of LED units is much more than HID but the running cost is cheaper and is more reliable - with bulbs lasting more than 50,000 hours.
Light Emitting Plasma (LEP) grow lights
Light Emitting Plasma grow lamps use a different technology to regular horticultural lighting. There are no moving parts or electrodes, so LEP units stably output a continuous spectrum reliably over time. The spectrum contains UVA and UVB and is mostly suited for vegetative phases, but use of LEP in the last two weeks of flower will increase both resin content and taste.
400 V vs 230 V
400 V lighting systems are a new development on the market that are regularly outperforming the results of 230 V systems. 400 V systems are a larger initial investment, but many growers realise the increased intensity of light these systems bring show in the end result, in terms of yield and quality.
Types of Reflectors
Euro reflectors are an entry-level reflector made from aluminium. Sometimes called barn reflectors, the units are open ended so some of the light is lost from the sides of the unit but the majority of light heading upward is captured by the reflector and directed down onto the plant canopy.
Adjust-a-wings are the top of the range reflector for standard 230v systems that allow the angle of the wings to be adjusted. The ability to adjust enables the spread and intensity of the light to be altered to maximise yield and reduce hotspots. When multiple lights with adjust-a-wings are used, the crossover of lights can be adjusted to maintain consistent light-levels across the canopy, leading to a more uniform crop.
Adjust-a-Wings Defender model is manufactured specifically for 400w and 600w bulbs. They are a medium sized reflector, perfect for a 1m2 or 1.2m2 tent.
Adjust-a-Wings Enforcer maintains all the benefits of the defender but it’s a large reflector that has been created for 1000w bulbs so is suitable for larger gardens such as 1.5m2 tents.
The Matrix reflector offers the benefits of an air-cooled reflector, without the use of glass that can block a percentage of the light as in most air-cooled reflectors. The reflector can either be actively cooled with use of extraction onto the reflector or the reflector will passively cool without any additional equipment as the hot air will rise out of the reflector, away from plants.
Parabolic reflectors hold the bulb in a vertical position, allowing for an even spread of diffused light resulting in a uniform canopy that can make use of all available light.
Our budget parabolic reflectors are available in two sizes, one with a diameter of 80cm and one with a diameter of 100cm so you can purchase one to fit your space. Our budget reflectors are gloss white so they reflect light in a diffused way, reducing hot spots and increasing an even distribution of light.
Air cooled reflectors
Air-cooled reflectors allow ducting to be attached to either side of the fixture. In this way, the bulb can be cooled with air running through the reflector and exhausted outside of the growing environment. This allows growers to keep their garden cool, which is especially important during the hot summer months as the same number of lights can be employed without increasing the rooms temperature.
Completely air tight so no leaks, Cool tubes are a budget air cooled reflector.
Goldstars are a traditional rectangular shape, so have a typical spread of light whilst maintaining the advantages of an air-cooled reflector.
Dominator XXXL Air Cooled Reflector
One of the largest reflectors on the market, the dominator XXXL can spread light from a 1000 W bulb over 1.5 m2.
Types of Ballast
Magnetic ballast use a tried and tested 60-year-old technology to regulate the electrical output to the bulb. Magnetic ballasts are only compatible with a single wattage of bulb. You need to get the exact wattage you require for your HPS or MH bulb. Magnetic ballasts are supplied in 250, 400, 600 and 1000 W. Magnetic ballasts are composed of an iron or steel block with a wrap of coiled copper surrounding the block. There's no moving parts or sensitive electronics so, as a result, magnetic ballasts often last decades.
Digital ballasts provide an alternative to the dependable magnetic ballast. The variable output means you can run a range of grow bulbs from a single unit. Simply selecting the power output means you can use 250, 400, 600 and 1000 W bulbs, some ballasts have an overdrive feature that allows the bulb to be driven at 1100 W. Digital ballasts use a soft start feature when igniting the bulbs, this allows the bulbs to run cooler, prolonging their life. Digital ballasts run cooler than magnetic ballast, resulting in less heat within the garden.
Digital ballasts can be supplied in 400 V or the standard 230 V model, make sure you match the correct voltage with the bulb.
Timers are essential for any grower. Timers allow you to precisely set the sunrise and sunset of an indoor garden. Timers work well for single light set ups, but with the high initial current demands of more powerful bulbs and systems running more than one light, we recommend using a contactor.
Contactors work in conjunction with timers and are a safer option when using HID lights. The initial start-up power requirements of HID lights can burn out or fuse the electrical components in the timers timing is separated. The majority of 24 Hour timers are not designed for high current switching and can fail when used with HID lighting loads. Contactors incorporate high-power relays to switch power to the lighting system. This removes the issues of using timers, as they are only used for timing control. Power for the lights is taken from a one wall socket, while the timer is situated in an adjacent socket.
Electronic controllers allow several lights to be manipulated from a single controller and allow for a soft start- up which should prolong lamp life. Controllers can also simulate sunrise and sunset by gradually altering the intensity of light output.
We offer a range of light hangers to easily install your lighting system onto the ceiling of your room or tent. Easyroll light hangers have a strong inbuilt spring that puts tension on the light allowing the gardener to effortlessly change the height the lighting system hangs at. Jack Chains provide a stronger solution for heavier equipment. Ratchet hangers are robust and can easily be tightened or loosened depending on the intended hanging height.
Jupiter light movers offer a range of solutions to increase your light’s footprint moving light fixtures across the top of the foliage canopy. Light movers have many benefits over stationary hangers, including increased coverage of the lamp, higher efficiency and an increased yield.
Our complete lighting kits provide everything needed to get your light source up and running. Lighting kits come packaged with the other components supplied in the kit, consisting of:
- Grow bulb
Here at future Garden, we offer a range of specialist horticultural brands. Entry-level brands provide the cheapest, cost-effective grow lights that do a very good job. While high-end brands use the highest-quality components, backed by leading-edge research and development processes to make their grow lights more reliable, consistent and longer lasting.
Maxibright have been manufacturing specialised horticultural equipment since 1996. They’re one of the most popular manufacturers on the market due to their high quality and fair pricing. They produce: HID bulbs, Fluorescent bulbs, Reflectors ballasts and Controllers. The complete Maxibright line-up is manufactured to British electrical safety standards.
Gavita supplies major horticultural businesses with lighting for large scale operations in greenhouses that span hectares for both edible and ornamental crops. The widespread use of Gavita’s lighting systems across the horticultural industry is testament to their reliable, effective and yield-boosting grow lights. While the range of Gavita products sit at the high-end of the market, they produce more lumens per watt than cheaper lighting systems, and increase final yields.
SANLight are a lighting innovation company, located in the west of Austria, in Vorarlberg. SANLight develop and manufacture efficient, sophisticated LED lights for commercial gardeners as well as for hobby purposes. Years of experience in horticulture and in-depth knowledge of photonics and semiconductor technology contribute to the development of their high-end products.
Dimlux have pioneered their alpha 98 reflector, which boasts the highest reflectivity of any reflector on the market. Dimlux ballasts come with seven dimmer stages allowing you more options and variability to match your plants requirements. Dimlux specialise in complete lighting kits, where the ballast, reflector and bulb are all included and will work together out of the box.
Osram have been in the lamp manufacturing game for over 100 years, fine-tuning the technology they use to create their products. They manufacture HPS, MH and CMH bulbs with several wattages to cater for most size of garden.
Philips are world-renowned for their high-quality electrical components. Their indoor horticulture bulbs maintain the same high standards. Philips invested in the Research and development of their 315 W Ceramic Metal Halide bulbs, culminating in one of the most technologically advanced, highest output per watt and longest lasting bulbs available on the market.
Sunmaster manufacture a range of bulbs including HPS, MH and Dual spectrum. These bulbs all have a different colour output so you can tailor the produced spectrum for optimum yields and accelerated growth through all stages of development.
If you need more info on our selection of grow lights, email us or call our specialist team on 0800 085 7995.