Feeding Rhubarb: When and What to Fertilize With

A lush rhubarb patch doesn’t just happen. Beneath those giant leaves and juicy stalks is a well-fed plant, nourished by smart, timely care. Feeding rhubarb properly means bigger, brighter, and more delicious harvests year after year. Here’s how to get your fertilizer timing, ingredients, and methods just right.

When to Feed Rhubarb

Spring (March–April, just before growth starts):

• This is the most important time to feed rhubarb. Early nutrition supports strong, rapid leaf and stalk growth.

After Main Harvest (June–July):

• A light feed or mulch helps replenish energy reserves for next year.

Autumn (Optional, after die-back):

• Add a layer of compost or manure to enrich the soil for next season.

The Best Feeds for Rhubarb

1. Well-Rotted Manure or Compost

• Mulch each spring with a deep layer (2–3″/5–8cm) of compost, leaf mold, or old manure.
• Feed slowly for steady, strong stalks and healthy crowns.

2. Balanced, Slow-Release Fertilizer

• NPK ratios around 5-5-5 to 10-10-10 suit rhubarb.
• Scatter granules in a ring 15–30cm (6–12”) from the crown, not touching the plant.

3. Blood, Fish, and Bone / Pelleted Organic Feeds

• Sprinkle lightly and water in at the start of growth and after harvest.

4. High-Potash Feed (e.g., Tomato Fertilizer)

• Use a small dose in early spring if you want even sweeter, deeper colored stalks.

Feeding Do’s and Don’ts

• DO mulch and feed every year for abundant, tender stalks.
• DO NOT heap manure or fertilizer directly over the crown or growing buds—this can cause rot.
• DO NOT overdo it. Too much nitrogen = lush leaves but weak or spindly stalks.
• DO water deeply after feeding.

Extra Feeding Tips

• Feed container rhubarb a balanced liquid feed every month from March to June.
• If stalks thin or plants weaken, feed and mulch and consider dividing crowns soon.

Feeding Rhubarb: Quick Calendar

• Early spring: Compost/manure mulch, slow-release organic or granular feed.
• Post-harvest: Light top-dress or diluted liquid organic feed.
• Autumn: Mulch again or add leaf mold for winter soil health.

Wrapping Up

Feeding rhubarb is a once-or-twice-a-year commitment with big rewards—think extra-juicy stalks and a long-lived, resilient patch. Skip the chemicals and stick with good compost, steady mulch, and smart fertilizer choices for luscious rhubarb every season.

⭐ Recommended Products — Garden & Allotment Essentials for March

March is when the growing season truly begins. Seeds are being sown daily, beds are prepared and late frosts are still possible — these essentials help produce strong plants and a successful start.

Seed Trays, Modules & Propagation Kits — perfect for tomatoes, brassicas, lettuce, onions and flowers. 👉 Click here to see top options

Heated Propagators, Heat Mats & Grow Lights — improves germination and prevents leggy seedlings during cold nights. 👉 Click here to see top options

Seed & Cutting Compost — essential for healthy seedlings and strong root growth. 👉 Click here to see top options

Garden Fleece & Plant Protection Covers — protects seedlings, potatoes and early plantings from late frost. 👉 Click here to see top options

Spring Vegetable Seeds — carrots, beetroot, peas, spinach and salads can all be started now. 👉 Click here to see top options

Garden Kneeler & Seat — makes long sowing and planting sessions far more comfortable. 👉 Click here to see top options

Pressure Washer (Greenhouse & Patio Cleaning) — clean patios, paths and greenhouses before planting. 👉 Click here to see top options

Solar Garden Lights — perfect for enjoying the garden during brighter spring evenings. 👉 Click here to see top options