Annuals that Spill Over

Thrillers, which are tall flowers that serve as focal points in containers, might be the first ones you think about when planting, but they are not the most important. When designing the perfect container planting, your focus should be on annuals that spill over the sides.

Referred to as “spillers,” these border plants provide creeping foliage to help create a softer look to the edges as it hides the straight edge of the flower boxes.

When designing your flower beds, you might opt for a taller plant like Salvia for the focal point, as the flower stalks reach up to five feet tall. Once the focal point is decided on, gardeners must fill in the rest of the container with ground cover or border plantings.

Creeping Jenny is an excellent choice for a ground cover style planting, as the foliage spreads out, creating a lime green carpet of leaves.

Trailing Coleus works well in hanging baskets and along edges of containers, while the bush style Coleus works best in the center of baskets and boxes.

Tips for Choosing Spiller Plants

Before you can choose the best spiller plant for your baskets, containers, or the best flowers for window boxes, you must consider the planting location. Picking the best spillers for your lighting requirements is essential.

Some spillers, such as Coleus and Fuchsia, work best in the shade while others like Ivy Geraniums or Sweet Alyssum are sun loving annuals.

You also need to consider your USDA Hardiness Zone, otherwise known as your growing zone, as not all plants can thrive in all areas of the United States.

To discover your growing region, look at the USDA Hardiness Zone Map, and then choose plants that match your location. Individual care conditions also necessitate consideration when determining the best spillers for your landscape.

Lighting specifications are just the start; you must also analyze soil conditions, watering demands, and whether any pruning is required for their care.

When choosing plants for containers, boxes, or baskets, group plants with similar care needs together to improve your chances of success.

Many people get stuck on a specific species of plant, but that severely limits their choices. Many of your favorite plants have many different varieties, although they belong to the same family.

However, some are best suited for spilling while others might grow upright and serve as a focal point. If you find an upright plant, you can’t say no to, but you really want a spiller, look carefully at the other classifications in the same family to see if there is a suitable substitution.

Attractive Annuals that Spill Over the Sides

When it comes to container gardening, some plants work better than others. For example, pansies and marigolds work well in window boxes, but not in hanging baskets as their foliage doesn’t drape over the sides.

Annuals that Spill Over – Sweet Alyssum (Alyssum maritimum)

If you grow the cool weather-loving Sweet Alyssum in a container, you can’t help but notice it doesn’t precisely trail down the sides. As it grows, Sweet Alyssum seems to flow along the edge of the container, as it’s a neat plant that doesn’t sprawl as it spreads.

When planting in containers or window boxes, regular watering is necessary for prolific blooms. Both heat and drought tolerant, Sweet Alyssum belongs to the mustard family of plants but gets its name from its pleasantly sweet fragrance.

Summer Snapdragon (Angelonia angustifolia)

Summer Snapdragons are easy to grow and care for, despite their delicate look. Technically not a member of the Snapdragon family, Summer Snapdragons are named after the strong resemblance their clusters of flowers have to actual Snapdragons.

Along the main stems of the plant are bluish-purple flower spikes. Blooms start appearing at the beginning of summer and continue to emerge until the fall.

The sweet fragrance emitting from the flowers is similar to apples. Deadheading keeps the plant looking healthy, but is not necessary for new blooms.

New Guinea Impatiens (Impatiens hawkeri)

A long-blooming annual, New Guinea Impatiens works well in full sun, even when used in hanging baskets. Thick five-petaled flowers sit on top of dark green, burgundy, or variegated glossy leaves.

The sweet nectar produced by the flowers attracts pollinators, but very few pests. New Guinea Impatiens needs little care but they do have to have regular watering and proper lighting.

In hotter climates, choose planting locations with morning sun and afternoon shade. They are not drought-tolerant plants; increase watering during hot temperatures and allow the soil to dry out in between watering.

Tuberous Begonias (Begonia tuberhybrida) – Spilling Annuals

If you want something showy for a hanging basket, window box, or garden container, the Tuberous Begonia is an excellent choice. The trailing style works splendidly as edging or border plants, while the upright variety serves as a focal point.

Choose from single or double flowers in numerous hues paired with burgundy or green foliage. When planting Tuberous Begonias, only do so when temperatures are over 50°F as colder temperatures damage it.

As the summer comes to an end, reduce watering as the plant begins to die back. Trim the foliage as it yellows and then dig up tubers to store inside during the winter.

Sweet Potato Vine (Ipomea batatas)

A popular ground cover plant, Sweet Potato Vine is also becoming a widespread option for container planting. Leaves range from green to chartreuse to almost black and look similar to oak leaves or offer a heart shape.

Although an ornamental vine, the tuber is edible if you wish to harvest it at the end of the season. Sweet Potato Vine thrives in hot climates, including deserts; it is also tolerant of humidity.

Plant this vine in well-draining soil in full sun for optimal growth. Light pruning and some shaping of the vine are necessary to prevent it from becoming invasive.

Nasturtium (Tropaeolum)

As a mounding style plant, Nasturtium is well-known for its leaves that look like lily pads and bright flowers. Nasturtiums prefer cooler temperatures for optimal blooming, but with enough water, you can expect blossoms all season long.

An even better surprise is that these annuals for hummingbirds are edible. In hanging baskets, opt for the trailing Nasturtium, while if you have boxes with a trellis, use the climbing ones.

Never use soil with added fertilizer for planting your boxes or baskets, as it decreases blooming. Only water until you begin seeing the water flow from the drainage holes. Allow the earth to dry out between watering.

Attractive Spilling Annuals – Vervain (Verbena)

Sometimes referred to as Tears of Isis, this spilling plant does well in hanging baskets or containers. A heat-tolerant plant, Vervain is known for its prolific blooming even during the first year of planting.

For the best blooms, plant in full sun, but partial shade in the afternoon is acceptable. Vervain adapts to a variety of soil conditions but expects good drainage.

As a finickier plant than others, it doesn’t tolerate neglect. Overwatering or poor drainage increases the risk of root rot, but not enough water leads to a quick death. Check Vervain soil daily to see if water is needed.

Fan Flower (Scaevola)

A tropical plant, Fan Flower is known for its weird-looking flowers set against deep green foliage. The flower petals resemble fans, as they only encompass half of the flower’s disc.

The light purple flowers work well with most color schemes, making it an excellent choice in any landscape.

Fan Flower isn’t prone to many pests or diseases and is self-cleaning, so deadheading spent blossoms is not necessary. These cascading flowers for hanging baskets need up to eight hours of sunlight a day and adapt easily to several soils.

Lobelia (Lobelia erinus)

Lobelia thrives during the spring months, as it prefers the moderate temperatures that spring provides. The green foliage is littered with tiny blue flowers that seem to spill from the sides.

Blooming is over before summer hits, and the foliage quickly dies off in the heat. Lobelia demands little care once it becomes established, but once the blooms are done, many gardeners prefer planting something else in its place.

This plant likes moist but not overly wet soil. Deadhead spent blossoms as they appear for a healthy look.

Fuchsia (Fuchsia magellanica) – Annuals that Spill Over

For areas with a lot of shade, add Fuchsia for a bright spot in the dark. When grown as annuals in baskets or boxes, use a pre-fertilized potting mix. Use a plant from your local garden center, as they are challenging to grow from seed.

Fuchsia doesn’t tolerate heat or full sun, so keep them in the shade, especially during heatwaves. Fuchsias must have a lot of water – lack of watering causes almost instant wilting and drying of the bright flowers.

Check the soil daily during hotter temperatures and water when the ground feels dry to the touch. Use a potting soil with moisture retention abilities or cover with a layer of mulch to keep moisture in.

Ivy Geraniums (Pelargonium)

This ivy form of Geraniums is known for its abundant blooms of small red flowers. There is nothing different in the blossoms that appear on the ivy form compared to the upright variety.

The ivy from spills gently over the edges of your bed or containers and tolerates heat and drought well. When planting Ivy Geraniums, choose a location with fertile and well-draining soil.

There are over 200 species of Ivy Geraniums – most begin blooming in the middle of spring and continue with occasional deadheading until the first frost.

Million Bells (Calibrachoa)

Million Bells or Trailing Petunias are easy to care for spillers that don’t expect deadheading. The spent flowers fall from the plant, and new ones appear with no extra work. As an extended bloomer, new flowers appear until the first frost hits.

Cascading foliage is dense rather than spindly. Million Bells thrives in full sun. For the best blooms on these best annuals for containers, avoid areas with afternoon shade or heavily shaded areas that receive just a dappling of sunlight.

For containers and baskets, use a soil-free mix that you amend with compost for the best drainage and always keep the potting mix moist.

Best Annuals that Spill Over – Water Hyssop (Bacopa monnieri)

The beautiful trailing design of the Water Hyssop makes it an excellent selection for filler in baskets and containers. The delicate-looking white or blue flowers rest upon green foliage, but don’t let this plant’s appearance trick you.

Despite how delicate the flowers look, this beauty is one of the most robust plants around. Water Hyssop is an herb that does well when planted with other herbs, but also works with ornamental grasses such as Purple Fountain Grass.

Keep the soil moist for Water Hyssop and choose a location with full sun to part shade. Plant this one along edges as it doesn’t grow upright but creeps down the sides.

Nemesia (Nemesia spp.)

Upon first glance, many people mistake Nemesia for Lobelia. Both these plants offer low-growing mounds with green foliage, but their flowers are quite different.

Nemesia flowers look like a small version of orchids, as the four petals on top form a fan shape with the larger petal on the bottom. To successfully grow Nemesia, use organically fertile soil that you keep moist, but that also has excellent draining capabilities.

Overly wet ground conditions lead to stem root. If possible, plant in full sun for the best blooms which appear from late spring until the end of fall.

Thank you for learning about our favorite flowering plants that spill over to provide interest to your landscape. If you thought any of our annual flowers were a good selection, please share our thoughts on the most attractive annuals that spill over with others on Facebook and Pinterest.