Growing begonias from pelleted seeds – white begonia flowers with dark foliage and pink tuberous begonias in bloom

Growing Begonias from Pelleted Seeds: A Complete Guide

Begonias are some of the most versatile and rewarding flowers to grow, known for their brilliant colors, unique foliage, and adaptability to both sun and shade. They are a favorite for hanging baskets, patio pots, garden beds, and combo planters. While many gardeners start begonias from plugs or tubers, growing begonias from pelleted seed offers unmatched flexibility and cost-effectiveness for both home gardeners and professional growers.

At our nursery, we start begonias in 288-cell plug trays using pelleted seed, which makes the process much easier, more efficient, and consistent. Pelleted begonia seed eliminates the challenge of handling dust-sized raw seed, ensuring uniform sowing and stronger germination rates.

This guide will cover everything you need to know about:

  • Why pelleted begonia seeds are the best choice for growers

  • Step-by-step sowing and germination instructions

  • Light, humidity, and moisture requirements

  • Finishing tips for transplanting into pots, baskets, and planters

  • Common pests, diseases, and how to avoid them

  • Key cultural practices for strong, colorful plants

👉 Shop our selection of Begonia Seeds on our regular site for smaller packs, or browse bulk begonia seeds for larger orders.

Why Choose Pelleted Begonia Seeds?

Raw begonia seed is incredibly small—so fine that even experienced growers struggle to sow it evenly. Pelleted seed solves this challenge by coating each seed in an inert material, forming a round pellet that’s easy to see and handle.

Benefits of Pelleted Begonia Seeds:

  1. Precision in Seeding – Pellets drop neatly into trays, reducing waste.

  2. Uniform Germination – Even spacing ensures plants develop consistently.

  3. Easier Handling – No more struggling with dust-like seed; pellets are visible.

  4. Professional Results – Standard in commercial plug production for uniform crops.

The only requirement is consistent moisture at the start, since the coating must fully dissolve before the seed can germinate.

How to Start Begonias from Pelleted Seeds

At our nursery, we start pelleted begonia seeds in 288-cell plug trays, sowing one seed per cell with a vacuum seeder. Here’s the process in detail:

Germination (Stages 1 & 2)

  • Germination time: ~14 days

  • Temperature: 72–78 °F (23–25 °C)

  • Light: Not required for germination

  • Seed cover: Do not cover seeds with media

  • Moisture: Keep media at level 5 – SATURATED. Soil should be dark brown, shiny, and heavy with visible water. This ensures the pellet dissolves completely.

  • Tray size: 288-cell tray

  • Seeds per cell: 1

Using a humidity dome during germination helps retain consistent moisture.

Young Plant Production (Stages 3 & 4)

Once seedlings emerge, they require careful management to grow into strong plugs.

  • Temperature: Day 70–72 °F, Night 68–70 °F

  • Light: Long-day plants, needing 14+ hours of light daily

  • Light intensity: 1,500–3,000 foot candles (300–600 μmol/m²/s)

  • Daily light integral (DLI): 8–10 mols/day

  • Moisture: Alternate between level 2 (medium dry) and level 4 (wet). This wet-dry cycle strengthens roots and prevents algae.

  • Fertilizer: 100–150 ppm N, applied consistently

  • pH: 5.5–5.9

  • EC: 0.5–0.75 mS/cm

Pinching: Not required for begonias.
Growth regulators (PGRs): Usually unnecessary, but for large plugs (72-cell), light sprays of Cycocel® (250 ppm) or B-Nine® (500–750 ppm) can help tone growth.

👉 Plug grow time: 7–9 weeks in a 288 tray before transplanting.

Finishing: Transplanting to Pots and Baskets

Once seedlings are ready, transplant directly into finished containers such as pints, quarts, gallons, or hanging baskets.

  • Transplanting tip: Place the plug slightly above media level to avoid crown rot.

  • Spacing: Center each plug for uniform growth. If planting multiple plugs per basket, angle leaves toward the rim to showcase flowers.

  • Temperature: Day 66–68 °F, Night 58–60 °F

  • Lighting: 2,000–4,000 foot candles, DLI of 10–12 mols/day

  • Fertilizer: 200–250 ppm N for finishing

  • Moisture: Maintain alternating level 2–4 cycles, never allowing constant saturation.

Exposure and Habit

Begonias thrive in a wide range of exposures, from full sun to shade. Their semi-trailing habit makes them especially attractive in patio pots, combos, and hanging baskets, but they perform equally well in garden beds.

  • Garden height: 12–16” (30–40 cm)

  • Garden width: 16–20” (40–50 cm)

  • Habit: Semi-trailing, upright with cascading flower clusters

Common Issues: Pests and Diseases

While begonias are relatively resilient, they can face certain challenges.

  • Pests: Fungus gnats, shore flies (during propagation), and thrips.

  • Diseases: Pythium and Botrytis, especially under poor moisture control.

Preventive Measures:

  • Irrigate early in the day to avoid leaf scorch.

  • Allow the media surface to dry slightly between waterings.

  • Maintain good airflow in greenhouses.

  • Avoid high ammonium fertilizers, which cause overly soft growth.

Cultural Tips for Success

  • Long days matter: Upright begonias respond to 14-hour days, which improve bloom set and plant quality.

  • Don’t bury plugs: Planting too deep can cause crown rot.

  • Moisture control: Avoid standing water and algae buildup by allowing soil to cycle between wet and medium dry.

  • Fertilizer management: Stick with balanced or nitrate-based feeds; avoid high ammonium formulas.

  • Retail impact: Begonias with pointed leaves toward the rim of a container create a fuller, more appealing look at garden centers.

Why Upright Begonias are Perfect for Containers

Unlike trailing types, upright begonias are excellent for bedding and container sales because they:

  • Grow into neat, rounded mounds.

  • Fill small retail pots quickly.

  • Perform well in both sun and shade conditions.

  • Offer long-lasting color throughout the summer.

They are especially popular in:

  • Patio pots – where their rounded form fills the container.

  • Hanging baskets – semi-trailing habit drapes elegantly over the edges.

  • Combo planters – pair well with foliage plants, grasses, or trailing vines.

Why Pelleted Begonia Seeds Are Best for Growers

For both home growers and professional greenhouses, pelleted begonia seeds are the gold standard. They provide precision, efficiency, and reliability that raw seed simply cannot match.

Whether you’re producing hundreds of plugs in a nursery or a handful of plants for a home garden, pelleted seeds give you a better start every time.

👉 Explore our collection of Begonia Seeds for smaller packs or shop Bulk Begonia Seeds for larger greenhouse and nursery orders.

Conclusion: Becoming Confident with Begonia Seed Starting

Growing begonias from seed may seem daunting at first, but with pelleted seed technology, proper germination practices, and the right cultural care, it’s easier than ever to raise healthy, vibrant plants.

By starting seeds in 288-cell trays, using humidity domes, maintaining proper moisture cycles, and following lighting and fertilization guidelines, both home gardeners and commercial growers can achieve professional results.

Whether you choose varieties for containers, hanging baskets, or patio planters, begonias grown from seed will reward you with non-stop blooms and strong garden performance.

🌸 Shop begonias today and discover the difference pelleted seed makes:

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