At The Greenhouse Effect we stock a large selection of additives and nutrients for hydroponic gardening.
If you need any help please call us on 01908 585 283, our highly knowledgeable staff will be happy to assist you.

Showing 1–36 of 327 resultsSorted by average rating

RAW Terpz

Original price was: £14.99 – £44.99Price range: £14.99 through £44.99.Current price is: £13.49 – £40.49Price range: £13.49 through £40.49.
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RAW Terpz

Techboost EX:EL Foliar Spray

Original price was: £18.99 – £52.99Price range: £18.99 through £52.99.Current price is: £17.09 – £47.69Price range: £17.09 through £47.69.
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Techboost EX:EL Foliar Spray

Veg + Bloom Push Foliar 1 Litre

Original price was: £84.99.Current price is: £76.49.
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Veg + Bloom Push Foliar 1 Litre

Ecothrive Bio-Blend

Price range: £10.79 through £53.99
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Ecothrive Bio-Blend

Ionic Flower Boost 1 Litre

Original price was: £74.99.Current price is: £67.49.
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Ionic Flower Boost 1 Litre

Ionic Root Boost 1 Litre

Original price was: £94.99.Current price is: £85.49.
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Ionic Root Boost 1 Litre

Athena Blended Starter Kit

Original price was: £123.99.Current price is: £111.59.
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Athena Blended Starter Kit

Veg + Bloom Shine Clean

Original price was: £38.99 – £749.99Price range: £38.99 through £749.99.Current price is: £35.09 – £674.99Price range: £35.09 through £674.99.
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Veg + Bloom Shine Clean

Hades 1 Litre

Original price was: £69.99.Current price is: £62.99.
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Hades 1 Litre

Xtreme Gardening Azos

Original price was: £36.99 – £64.99Price range: £36.99 through £64.99.Current price is: £33.29 – £58.49Price range: £33.29 through £58.49.
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Xtreme Gardening Azos

Psycho Myco Monster Microbes

Original price was: £59.99 – £189.99Price range: £59.99 through £189.99.Current price is: £53.99 – £170.99Price range: £53.99 through £170.99.
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Psycho Myco Monster Microbes

Psycho Myco Momma Myco

Original price was: £42.99 – £99.99Price range: £42.99 through £99.99.Current price is: £38.69 – £89.99Price range: £38.69 through £89.99.
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Psycho Myco Momma Myco

Psycho Myco Grow Balls

Original price was: £42.99 – £89.99Price range: £42.99 through £89.99.Current price is: £38.69 – £80.99Price range: £38.69 through £80.99.
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Psycho Myco Grow Balls

Canna Silica 1 Litre

Original price was: £17.99.Current price is: £16.19.
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Canna Silica 1 Litre

Moonshine Sunshine RTU 1 Litre

Original price was: £13.99.Current price is: £12.59.
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Moonshine Sunshine RTU 1 Litre

House and Garden Algen Extract

Original price was: £19.99 – £64.99Price range: £19.99 through £64.99.Current price is: £17.99 – £58.49Price range: £17.99 through £58.49.
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House and Garden Algen Extract

Terra Aquatica Calcium Magnesium

Original price was: £12.99 – £32.99Price range: £12.99 through £32.99.Current price is: £11.69 – £29.69Price range: £11.69 through £29.69.
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Terra Aquatica Calcium Magnesium

Vitalink Foliar 5 Litre

Original price was: £69.99.Current price is: £62.99.
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Vitalink Foliar 5 Litre

Dutch Pro Quantum Massive Powdershot

Original price was: £13.99 – £159.99Price range: £13.99 through £159.99.Current price is: £12.59 – £143.99Price range: £12.59 through £143.99.
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Dutch Pro Quantum Massive Powdershot

Canna Bio Rhizotonic

Original price was: £12.99 – £29.99Price range: £12.99 through £29.99.Current price is: £11.69 – £26.99Price range: £11.69 through £26.99.
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Canna Bio Rhizotonic

Canna Bio Boost

Original price was: £19.99 – £49.99Price range: £19.99 through £49.99.Current price is: £17.99 – £44.99Price range: £17.99 through £44.99.
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Canna Bio Boost

Bio Green Lime 5KG

Original price was: £18.99.Current price is: £17.09.
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Bio Green Lime 5KG

Mammoth P by Growcentia

Original price was: £79.99 – £189.99Price range: £79.99 through £189.99.Current price is: £71.99 – £170.99Price range: £71.99 through £170.99.
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Mammoth P by Growcentia

Intense Nutrients Fem Guard

Original price was: £24.99 – £99.99Price range: £24.99 through £99.99.Current price is: £22.49 – £89.99Price range: £22.49 through £89.99.
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Intense Nutrients Fem Guard

Diamond Density

Original price was: £39.99 – £119.99Price range: £39.99 through £119.99.Current price is: £35.99 – £107.99Price range: £35.99 through £107.99.
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Diamond Density

FloraMax Growth-XS

Original price was: £95.99 – £1,151.99Price range: £95.99 through £1,151.99.Current price is: £86.39 – £1,036.79Price range: £86.39 through £1,036.79.
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FloraMax Growth-XS

Density Weight Finisher 5 Litre

Original price was: £199.99.Current price is: £179.99.
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Density Weight Finisher 5 Litre

Plagron Pure Zym

Original price was: £19.99 – £89.99Price range: £19.99 through £89.99.Current price is: £17.99 – £80.99Price range: £17.99 through £80.99.
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Plagron Pure Zym

Plant Magic Water Soluble Mycorrhizal

Original price was: £26.99 – £113.99Price range: £26.99 through £113.99.Current price is: £24.29 – £102.59Price range: £24.29 through £102.59.
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Plant Magic Water Soluble Mycorrhizal

Grow Genius Water Genius 100ml

Original price was: £24.99.Current price is: £22.49.
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Grow Genius Water Genius 100ml

Atami ATA Clean

Original price was: £19.99 – £89.99Price range: £19.99 through £89.99.Current price is: £17.99 – £80.99Price range: £17.99 through £80.99.
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Atami ATA Clean

Field Marshall Bliss Bud 5 Litre

Original price was: £149.99.Current price is: £134.99.
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Field Marshall Bliss Bud 5 Litre

Super Boost Foliar Spray

Original price was: £26.99 – £65.99Price range: £26.99 through £65.99.Current price is: £24.29 – £59.39Price range: £24.29 through £59.39.
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Super Boost Foliar Spray

New Millenium Winter Frost

Original price was: £49.99 – £154.99Price range: £49.99 through £154.99.Current price is: £44.99 – £139.99Price range: £44.99 through £139.99.
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New Millenium Winter Frost

New Millenium Ruby Ful#$% 1 Litre

Original price was: £29.99.Current price is: £26.99.
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New Millenium Ruby Ful#$% 1 Litre

Plagron Calmag Pro

Original price was: £19.99.Current price is: £17.99.
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Plagron Calmag Pro