Best Fall Bulb Fertilizer (5-10-10): High P & K to Build Root Reserves Before Winter Dormancy Buy on Old Cobblers Farm
Old Cobblers Farm™ Wicked Growth Fall Bulb Fertilizer
by Wicked Growth — Littleton, NH
Built for Bulb Biology
Bulbs planted in fall need root development, not leaf growth. 5% nitrogen stays low enough to avoid triggering foliage before winter, while 10% P and 10% K build the underground infrastructure.
10% Phosphorus for Root Establishment
Phosphorus drives the rapid root growth bulbs need during the fall rooting window. Strong roots mean better water and nutrient uptake when spring arrives.
10% Potassium for Energy Storage
Potassium helps bulbs store carbohydrates and regulate water balance heading into dormancy. Well-charged bulbs produce larger flowers with stronger stems.
Per-Bulb or Per-Bed Rates
1–2 tablespoons per individual bulb planting hole, or 1–2 lbs per 100 sq ft broadcast over entire bulb beds. Flexible for any planting method.
320 Bulbs Per Bag
At 1 tbsp per bulb, one 5 lb bag fertilizes up to 320 individual bulb plantings. For beds, covers 250–500 sq ft.
Fall + Spring Schedule
Apply at fall planting to fuel root growth, then top-dress again at spring emergence to support stem elongation and bloom development.
All Bulb Types
Tulips, daffodils, crocuses, hyacinths, alliums, lilies, muscari, snowdrops, fritillaria — every fall-planted bulb benefits from this P & K-forward formula.
Trusted by 20,000+ Growers
Developed in Littleton, New Hampshire. Sold nationwide on Amazon, Walmart, eBay, and theoldcobblersfarm.com.
| NPK Ratio | 5-10-10 |
| Derived From | Urea, Diammonium Phosphate, Muriate of Potash, Silicon Dioxide |
| Item Form | Granular |
| Release Speed | Moderate-release |
| Application Rate | 1–2 lbs / 100 sq ft | 1–2 tbsp / plant |
| Method | Incorporate into planting hole or broadcast over bed |
| Frequency | 1x at fall planting + 1x at spring emergence |
| Sizes | 5 lb | 10 lb | 15 lb | 20 lb |
| Supports | Tulips, daffodils, crocuses, hyacinths, alliums, lilies, muscari, snowdrops, fritillaria, iris |
| Setups | Bulb beds, borders, naturalizing areas, containers, under trees |
| Feature | Old Cobblers Farm™ Wicked Growth Fall Bulb Fertilizer | Bulb-Tone Organic | Bloom Booster Flower Food | All Purpose 5-10-5 | Great Gardens | Gro-Fine All Purpose | Nutra Green | Balanced Fertilizer | 10-10-10 All Purpose | Bulb Food Spikes | Flower & Vegetable |
|---|---|---|---|---|---|---|---|---|---|---|---|
| NPK | 5-10-10 | 4-6-2006 | 10-52-10 | 5-10-2005 | 5-10-2005 | 5-10-2005 | 5-10-2005 | 18-18-18 | 10-10-10 | 3-5-2004 | 10-10-10 |
| Phosphorus | 10.0% | 6.0% | 52.0% | 10.0% | 10.0% | 10.0% | 10.0% | 18.0% | 10.0% | 5.0% | 10.0% |
| Potassium | 10.0% | 6.0% | 10.0% | 5.0% | 5.0% | 5.0% | 5.0% | 18.0% | 10.0% | 4.0% | 10.0% |
| Form | Granular | ||||||||||
| Sizes | 5 lb | 10 lb | 15 lb | 20 lb | 4 lb, 18 lb | 1.5 lb | 40 lb | 20 lb | 18 lb | 1 Quart | 50 lb | 40 lb | 50 count | 3 lb |
| Release Speed | Moderate-release |
Bulb-Tone Organic
Bloom Booster Flower Food
All Purpose 5-10-5
Great Gardens
Gro-Fine All Purpose
Nutra Green
Balanced Fertilizer
10-10-10 All Purpose
Bulb Food Spikes
Flower & Vegetable
Built for Bulb Biology
Bulbs planted in fall need root development, not leaf growth. 5% nitrogen stays low enough to avoid triggering foliage before winter, while 10% P and 10% K build the underground infrastructure.
10% Phosphorus for Root Establishment
Phosphorus drives the rapid root growth bulbs need during the fall rooting window. Strong roots mean better water and nutrient uptake when spring arrives.
10% Potassium for Energy Storage
Potassium helps bulbs store carbohydrates and regulate water balance heading into dormancy. Well-charged bulbs produce larger flowers with stronger stems.
Per-Bulb or Per-Bed Rates
1–2 tablespoons per individual bulb planting hole, or 1–2 lbs per 100 sq ft broadcast over entire bulb beds. Flexible for any planting method.
