Mills C4 Bloom Booster Nutrient
Mills C4 is a bloom-stage booster nutrient formulated with macro and micro nutrients, bio-stimulants, carbohydrates and trace minerals to support stronger flowering and fruiting performance. Suitable for a wide range of growing methods, it is available in 250ml, 1L and 5L sizes.
- ✔ Designed for use from week 2 to week 6 of the bloom stage
- ✔ Contains macro and micro nutrients, bio-stimulants, carbohydrates and trace minerals
- ✔ Supports heavier flower and fruit development with improved density
- ✔ Encourages essential oil and sugar production during flowering
- ✔ Suitable for hydroponic systems and other growing media
- ✔ Available in 250ml, 1L and 5L bottle sizes
Price range: £45.50 through £179.50 incl. Vat
🌱 Mills C4 Bloom Booster Nutrient — Guide and Product Information
What is Mills C4?
Mills C4 is a flowering and fruiting booster developed to support plant performance during the bloom stage. This advanced nutrient blend combines macro and micro nutrients with bio-stimulants, carbohydrates and trace minerals to help growers push for improved flower set, better fruit development and stronger crop quality.
It is designed for growers working in hydroponic systems as well as other growing methods, making it a flexible option for flowering plants, fruiting crops and general horticultural use.
Key Benefits During Bloom
Used at the right stage of flowering, Mills C4 helps support more productive bloom development while promoting overall plant vitality. The formulation is intended to assist with denser flower and fruit formation, while also encouraging the production of oils and sugars.
- ✔ Supports quicker and more abundant fruit set
- ✔ Promotes active plant growth during bloom
- ✔ Helps encourage denser, harder and heavier flowers and fruits
- ✔ Enhances plant vitality during the flowering phase
- ✔ Stimulates oil and sugar production
📦 Available Options and Sizes
Mills C4 is a variable product with the following size options:
- ✔ 250ml
- ✔ 1L
- ✔ 5L
These size choices make it easier to select the right bottle for smaller grow spaces, trial use or larger-scale feeding routines.
Suitable Applications
Mills C4 is intended for use from the second week of bloom through to the sixth week. It can be used across different growing systems without needing to match it to one specific medium, making it suitable for hydroponics and other cultivation methods.
If you are exploring more products in this area, browse our Nutrients and Boosters range. You may also be interested in complementary products such as PLAGRON Terra Bloom Flowering Nutrient, PLAGRON Sugar Royal 5L or PLAGRON PUREZYM Enzyme Additive for Root Zone.
For more advice on getting the most from your feeding programme, read Boosting Plant Nutrition with Advanced Grow Kit Techniques.
Technical Specifications
Product:
Mills C4
Product Type:
Variable nutrient and booster product
Category:
Nutrients and Boosters
Use:
Bloom-stage booster nutrient
Application Stage:
From week 2 to week 6 of bloom
Suggested Dose:
4 to 8 ml per gallon
Suitable Growing Methods:
Hydroponics and other growing methods
Available Sizes:
250ml, 1L, 5L
Ideal Uses
- ✔ Supporting flowering plants during the mid-bloom period
- ✔ Encouraging improved fruit set in horticultural crops
- ✔ Feeding hydroponic systems and mixed growing setups
- ✔ Growers looking for a bloom additive that fits different media and watering methods
Setup and Usage Tips
Use Mills C4 during the flowering stage from week 2 until week 6. A rate of 4 to 8 ml per gallon is indicated in the product information. As with any nutrient or booster, it is good practice to mix thoroughly, monitor plant response and keep your wider feeding schedule balanced.
Stable environmental control also plays an important part in bloom performance. For helpful growing advice, you can also read The Role of Grow Lighting in Hydroponics: Maximising Yield and Nutrient Absorption.
Frequently Asked Questions
What does Mills C4 do?
Mills C4 is a bloom booster nutrient designed to support flowering and fruiting by providing a blend of macro and micro nutrients, bio-stimulants, carbohydrates and trace minerals.
When should I use Mills C4?
It is intended for use from the second week of the bloom stage through to the sixth week.
How much Mills C4 should I use?
The supplied guidance indicates 4 to 8 ml per gallon. Always mix carefully and adjust within a sensible feeding programme for your plants.
Is Mills C4 only for hydroponics?
No. The product description states that it is suitable whether you are growing hydroponically or using other methods and media.
What sizes are available?
Mills C4 is available in 250ml, 1L and 5L sizes, so you can choose the most practical option for your grow setup and feed schedule.
What kinds of plants is it suitable for?
It is described as suitable for flowers, agriculture and fruits, making it a versatile bloom-stage additive for a wide range of horticultural crops.

