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250g Bulb Starter with Rootgrow™

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Enjoy flourishing plants come spring with this RHS-endorsed Rootgrow

Rootgrow™ has become a planting essential for professional and amateur gardeners alike who want to ensure that their bulbs get off to the best start possible. Sprinkle a little when planting to ensure fantastic root growth and all the advantages that come with it. Plants rely on on a vast array of soil microbes to produce and exchange all of the nutrients required for healthy growth, and the most remarkable of these are the mycorrhizal fungi. The benefits of this bulb starter include the following:

  • Superior water and nutrient uptake with enhanced natural vigour.
  • More abundant flowers.
  • The need for less synthetic fertiliser.
  • Improved resilience to dry conditions.
  • A greater resistance to disease.

Application information
Follow these simple steps to planting success with Rootgrow™

  • 1. Dig planting holes at the depth and distance recommended in your bulbs' packaging.
  • 2. Sprinkle the granules over the bottom of the planting hole (using enough granules to cover only that area), and do not mix in.
  • 3. Place the bulbs in their planting holes so they are directly on top of the granules. It is important that the granules come into direct contact with the plant roots.
  • 4. Fill the planting hole as normal with compost or soil, and provide a watering. Also make sure that there are no air gaps near the bulbs.
  • 5. If using additional fertiliser, apply as a top dress or in backfill.
  • 6. Add mulch or top dress as required. 

Mycorrhizal Fungi and Your Plant

This quick video will give you a better understanding of what Mycorrhizal Fungi is and how it can help your plant. This remarkable symbiotic relationship will work wonders for your garden.

How Does It Work?

Once joined with the plant, this fungi will travel through the soil, creating a significant root system. This 'hybrid' root system is highly efficient at finding nutrients from places where a plant's root cannot travel, releasing soil bound chemicals (including those from our trusted fertilisers), and transporting these back to its partner. As such, a beneficial relationship is created that will persist throughout the life of the plant.

Supported by the Royal Horticultural Society

RHS Gardeners endorse Rootgrow™ because Rootgrow™ treated plants establish better with more vigour, replant more successfully, have better developed root systems, and cope better with drought conditions.

  • Small bulbs or corms: Use 10 - 15g
  • Large bulbs or tubers: Use 10 - 20g

Note: one palm full is approximately 10g

Primrose is the place to be to Discover Everything Garden.

We were created in 2003 to become the UK's largest online-only garden centre. Thousands of plants, planters, awnings, garden furniture sets, water features and more line our digital shelves, and we're ready to fill your garden with comfort, quality, colour and style.

If you'd like to find out more, check out our 'About Us' page.

We want you to be happy with your purchase from the moment it arrives, but if you aren't you have the right to return it within 14 days. Just head to our Returns Page, send us an email, receive a returns number and fire your product back to us.

We'll refund the full cost as well as standard delivery.

Highlands and Islands

We calculate delivery costs at checkout based on your entered postcode, so you'll know at that stage if your chosen product can be sent to you. If you have any queries, please head to Contact Us and send over a form, or visit our Help Centre.

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More Information
Is Collection/Mix? No
Needs Ericaceous Compost? No
Size 250g
Type Fertiliser, Mycorrhizal Fungi
Fertiliser Type Granular
Quantity 250g
Shop By Category Compost & Fertiliser