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Jack's Bloom Booster

Jack's Bloom Booster

MYKE Flower - 1L

MYKE Flower - 1L

Jack's Classic All Purpose

  • Great for keeping plants healthy in greenhouses and garden centers
  • Offers quick green-up
  • Significant foliar expansion
  • High levels of urea and ammonium nitrogen
  • Balanced phosphorus and potassium
  • Very good for root and shoot growth
  • Nitrogen 20%, Phosphate 20%, Potassium 20%
Jack's Classic All Purpose
Grouped product items
Product Name Qty
Jack's Classic All Purpose - 8 oz
Jack's Classic All Purpose - 1.5 lbs


The balanced formula of Jacks Classic All Purpose 20-20-20 can be used on a range of growing materials. Almost any stage of plant growth can benefit from its 1:1:1 nutrient ratio. The design of the formula makes use of plant nutrients that give the plant vigor as well as vibrant green growth. To provide the plant a boost of well-balanced nourishment, Jacks Classic All Purpose 20-20-20 can be applied either continuously as a liquid feed or periodically, alternately with water or rain.

It should preferably be applied to soil-based rather than soilless media, and only in warm climates or inside during the warmer months. These conditions make it possible for the roots to absorb nitrogen sources most efficiently. In some plant kinds, prolonged usage of high-phosphorus formulations might cause plant stretching. Therefore, it is advised to alternate utilizing Jacks Classic 20-20-20 with a lower phosphorous source, such as rainwater, calcium nitrate, or other lower phosphorus fertilizers, when using it for extended periods of time (more than 3–4 months) of plant growth.

This fertilizer can be applied as a foliar spray or as a root drench. When sprayed at the prescribed rates, the nutrient package in the All-Purpose 20-20-20 is designed for the leaves to absorb the nutrients most effectively; however, a root drench is just as effective and will leave little to no salt buildup in the medium.


Jacks Classic All Purpose
- Great for keeping plants healthy in greenhouses and garden centers
- Offers quick green-up
- Significant foliar expansion
- High levels of urea and ammonium nitrogen
- Balanced phosphorus and potassium
- Very good for root and shoot growth
- Nitrogen 20%, Phosphate 20%, Potassium 20%


Jacks Classic All Purpose
Brand: Jack's Nutrients
NPK: 20-20-20
Nutrient Type: Water Soluble
Net Wt: 8 oz. / 1.5 lbs

Mixing Instructions: (For small-volume mixing)
- Dissolve the following amounts in 1 gallon of water.
1/2 tsp. = 125 ppm
1 tsp. = 250 ppm
1 tbsp. = 750 ppm

WARNING: An injector should not be used.


- Canadian Garden Supply Grow Tents
- Canadian Garden Supply Plant Nutrients
- Canadian Garden Supply Reservoirs & Hydro Systems
- Jacks Classic All Purpose Safety Data Sheet
- Jack’s Nutrition Schedule
- Jack’s 321 Technical Bulletin


- Intro to Jack's Nutrients
- Getting Technical - Decoding a Nutrition Schedule
- Jack's Nutrients Hemp and Cannabis Questions Answered
- Jack'd Up Gardening #9 - Herbs


The Jack's Nutrients lineup is comprised of the FeED and BOOST products to offer you an efficient powdered solution that delivers the exact nutrient balance according to the crop's requirements.

Our onsite laboratory is the heart of our fertilizer family, the process always begins in the lab. What we have seen over the last few years is a great influx of people looking for some knowledge about how to get started with their operation without the confusion of consultants or hours spent on the web. From there, we started focusing our hydroponic and cannabis growers on a testing program that helps them navigate how to get started growing.

Jack's Nutrients Hydro Track and Nutrient Track programs are designed to be a tool kit of knowledge for a grower. Both new growers and those who have quite a bit of experience learn to understand what they are starting with in regard to their fertility. These testing kits create a blueprint on how to grow your plants and what nutrients and additions you may need to use. The technical support team at JR Peters then helps guide the grower to nutritional success.


All plants need three primary base nutrients on a regular basis throughout their life cycle: nitrogen (N), phosphorus (P), and potassium (K). These three macro-nutrients are usually displayed on the packaging of plant nutrients as NPK ratio.

Nitrogen (N) - Nitrogen is very mobile in the soil, and nitrogen in the form of nitrate has a tendency to leach away from the root zone. Nitrogen can also be lost to the atmosphere. Certain fertilizers, particularly urea, are easily converted to volatile forms of nitrogen if they are watered or incorporated into the soil after application. Soil testing for nitrogen is unreliable because it is so mobile in the soil. Timing of nitrogen fertilizer application should be crop-specific Excessive nitrates in drinking water are an environmental concern—another reason to maximize nitrogen utilization by plants and minimize excessive applications.

Phosphorus (P) - Phosphorus is essential in energy transformations in the plant. Without adequate phosphorus, carbohydrates manufactured in the leaves could not be transported to the flower or developing fruit, or stored in roots or bulbs. Phosphorus is usually associated with flowers, fruiting, and carbohydrate storage in roots, tubers, and bulbs.

Potassium (K) - Potassium is essential for photosynthesis, as regulation of cell turgidity, respiration, and water movement in the plant. It also controls the opening and closing of the plant’s stomata. Adequate potassium fertilization helps plants cope with drought stress, increases disease resistance, improves winter hardiness, and improves crop quality.


If you're here to buy Jacks Classic All Purpose or any other hydroponic products for your indoor growing needs know that we back up all products with support and best price guarantee. We thank you for making Canadian Garden Supply hydroponics store your online hydroponic grow store of choice.


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