Eye-catching hanging basket filled with Wave Petunias, Trailing Lobelia, and Dichondra Silver Falls used as fillers for lush, colorful baskets.

Best Fillers to Grow from Seed for Hanging Baskets with Wave Petunias

The Secret to Show-Stopping Hanging Baskets

Wave® Petunias and trailing petunias are legendary for their vibrant color, nonstop blooms, and cascading habit. But what really makes a 12-inch basket look lush and professional is the choice of fillers and companions. In our nursery, we start thousands of baskets each spring by sowing seed in 200-cell trays with a vacuum seeder. We plant 3–4 plugs of fillers around Wave Petunias to create full, balanced, and eye-catching displays that last from early summer until frost.

If you’re a grower, garden center, or home gardener looking to add the right seed-grown fillers, this guide explores the very best options — from Lobelia to Bacopa — and how to combine them with trailing petunias for stunning baskets.


🌿 Why Fillers Matter in Hanging Baskets

Fillers do more than “fill space.” They:

  • Add texture and contrast to the bold blooms of petunias.

  • Provide trailing interest that spills over the basket.

  • Extend bloom time by mixing in cool- or heat-loving companions.

  • Increase resale appeal — mixed baskets sell faster and for a higher margin than single-variety baskets.

In short: the right filler turns a petunia basket into a showpiece.


🌸 Top Seed-Grown Fillers for Hanging Baskets

Here are some of the very best fillers you can grow from seed that pair beautifully with Wave® and trailing petunias.


1. Trailing Lobelia

👉 Shop Trailing Lobelia Seeds

Few fillers can match Lobelia for delicate texture and color contrast. With clouds of tiny blue, purple, or white flowers, it softens the bold look of petunias and cascades gracefully over the edges of a basket.

  • How we grow it: Started in 200-cell trays, Lobelia germinates quickly and is easy to transplant. We add 3–4 plugs per 12” basket around the petunia plugs.

  • Why it works: It thrives in cooler temps, making it perfect for spring and early summer sales.


2. Trailing Vinca (Cora® Cascade)

👉 Shop Trailing Vinca Seeds

Cora Cascade Vinca is a heat-loving workhorse that keeps flowering in mid-summer heat when other fillers slow down. Available in pink, purple, and white, its glossy foliage and bright flowers provide strong contrast with petunias.

  • How we grow it: Seed is sown in plug trays, with plugs planted alongside Wave Petunias for baskets that last into late summer.

  • Why it works: Excellent drought and heat tolerance — perfect for southern growers or hot retail locations.


3. Trailing Verbena

👉 Shop Trailing Verbena Seeds

Verbena adds clusters of nectar-rich blooms in shades of purple, pink, and red. It attracts pollinators and pairs beautifully with petunias for a vibrant, cottage-style basket.

  • How we grow it: Seeds are started in plug trays and transplanted into baskets along with petunia plugs.

  • Why it works: Long bloom season, trailing habit, and toughness make Verbena a strong filler for retail-ready baskets.


4. Ivy Geraniums

👉 Shop Ivy Geranium Seeds

Ivy Geraniums are a classic choice for baskets, providing large, showy flowers with trailing vines of ivy-shaped leaves. They create an old-fashioned, elegant basket when combined with petunias.

  • How we grow it: Started in plug trays and grown on in warm conditions before transplanting into baskets.

  • Why it works: Adds big, bold flowers that stand up in mixed plantings.


5. Bacopa (Sutera cordata)

👉 Shop Bacopa Seeds

Bacopa is famous for its tiny white blooms that blanket a basket. It’s a spiller that keeps petunia baskets looking lush and balanced.

  • How we grow it: Sow seeds in 200-cell trays. Plugs are tucked into baskets as an edging plant.

  • Why it works: Its delicate appearance enhances the bold look of petunias without competing with them.


6. Alyssum

👉 Shop Alyssum Seeds

Sweet Alyssum offers fragrance plus a carpet of tiny flowers in white, lavender, or pink. It’s a low-maintenance filler that spills gently over the basket.

  • How we grow it: Easy to sow and quick to germinate, Alyssum is a perfect “speed crop” for filling baskets quickly.

  • Why it works: Fragrance plus bee-attracting flowers make it a customer favorite.


7. Dichondra ‘Silver Falls’

👉 Shop Dichondra Seeds

This foliage plant offers a shimmering waterfall effect. Its silvery leaves trail over a basket edge for dramatic texture.

  • How we grow it: Germinates easily and grows quickly in trays. Use 2–3 plugs per 12” basket with petunias.

  • Why it works: It adds contrast and spill — customers love the elegant silver look.


8. Coleus

👉 Shop Coleus Seeds

Coleus provides foliage in bold shades of chartreuse, burgundy, pink, and red. It anchors the basket with upright habit while petunias spill.

  • How we grow it: Sown in 200-cell trays and transplanted as center fillers in baskets.

  • Why it works: Adds foliage interest, especially when paired with flowering spillers like Lobelia and Bacopa.


🌼 Planting Method: How We Build Our Hanging Baskets

  • Step 1: Sow fillers and petunias in 200-cell trays using a vacuum seeder for uniform germination.

  • Step 2: Grow plugs to transplant stage (4–6 weeks).

  • Step 3: Plant 3–4 filler plugs around the edge of a 12” basket, with 3–5 petunia plugs in the center.

  • Step 4: Pinch and fertilize regularly for fullness.

  • Step 5: By early spring, baskets are lush, colorful, and ready for retail or display.


🌺 Other Combinations to Try

  • Wave Petunia + Bacopa + Dichondra for silver-and-purple elegance.

  • Wave Petunia + Trailing Lobelia + Alyssum for soft, pastel appeal.

  • Wave Petunia + Coleus + Verbena for bold color with structure.

  • Wave Petunia + Ivy Geranium + Trailing Vinca for a long-lasting, heat-tolerant combo.


🌱 Where to Find These Seeds


Conclusion

Wave Petunias may be the stars of the show, but the fillers you choose make or break a hanging basket. By adding seed-grown options like Lobelia, Bacopa, Verbena, and Coleus, you can create lush, colorful, and profitable baskets that keep customers coming back every season.

Whether you’re sowing thousands of plugs with a vacuum seeder or just planting a few baskets at home, these fillers will help you create truly show-stopping hanging baskets.

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