We're offering you a Chempak Onion Fertiliser 750g x 1 Unit for £6.99, saving you up to 22% off Thompson and Morgan's's price of £8.99 (correct as of 19.08.2025).

Organic Granular Fertiliser

Nourish Your Onions for Bigger, Better Harvests!

• Chempak Onion Fertiliser is expertly crafted to support the unique needs of onions, shallots, garlic, and leeks. With a precise N:P:K ratio (6-5-7 + 4MgO), this granular fertiliser delivers essential nutrients right where your alliums need them most.
• The slow-release formula ensures your crops receive a steady supply of nourishment throughout the season—no more nutrient surges or drops. Expect stronger growth and improved flavour in every bulb.
• A single kilogram covers up to 75 onion sets in a generous 7.5m (25ft) row, making it cost-effective and efficient for both small gardens and larger allotments.

How to Use

• Application: Evenly sprinkle the fertiliser along your planting rows before sowing or planting out onion sets, shallots, garlic, or leeks.
• Topping Up: For best results, lightly work into the soil and water well after application.
• Cropping Advice: Use on outdoor-grown alliums from early spring onwards. Avoid overfeeding—one application per season is usually sufficient.

Cultivation & Care Tips

• Soil: Prefers fertile, well-drained soil with a neutral to slightly alkaline pH (6.0–7.0).
• Sunlight: Plant in full sun for optimal bulb development.
• Irrigation: Water regularly during dry spells but avoid waterlogging.
• Companion Planting: Pairs well with carrots and beetroot—avoid planting near legumes.

Packed for Convenience

• Your order includes one handy 750g pack—easy to store and simple to use throughout the season.

FAQs

• Q: When should I apply this fertiliser?
  A: Apply just before planting onion sets or sowing seeds in early spring for best results.
• Q: Is this fertiliser suitable for other vegetables?
  A: It's specially formulated for onions, shallots, garlic, and leeks but can also benefit similar alliums grown outdoors.
• Q: How much do I need for my garden?
  A: One kilogram treats up to 75 onion sets along a 7.5m (25ft) row—adjust quantities according to your planting area.