Planting flowers in May might feel a bit late to some gardeners, but there is still plenty of time to create a vibrant, colorful space that lasts through summer. Many fast-growing and heat-tolerant plants can be sown or transplanted this month, making it easy to fill your beds, containers, and borders with blooms. Whether you are starting from seed or picking up young plants, these options are well-suited for warm-weather success. Here are the best flowers you can still plant now to enjoy bright, healthy blooms all season long.
1. Ageratum
Ageratum is a compact plant with fuzzy, blue to purple flowers that bloom steadily through summer. It does well in full sun to light shade and prefers moist, well-drained soil. You can start seeds in May or use young plants for faster results. Ageratum is great for borders and containers and attracts butterflies. It blends well with other annuals and keeps blooming with regular care.
2. Marigolds
Marigolds are hardy, easy-to-grow flowers that bring a burst of color to summer gardens. Once established, they do well in hot, sunny spots and can handle dry conditions. French and African marigolds are the most common types, offering bold yellow, orange, and red blooms. These flowers also help repel some garden pests, making them a smart companion plant. Sow the seeds directly in the ground or start them in containers for fast results.
3. Cosmos
Cosmos are airy, daisy-like flowers that grow easily from seed and thrive in heat. They do best in full sun and tolerate poor soil, making them a good choice for low-maintenance gardens. Once they begin to bloom, they continue all summer with minimal care. Cosmos attract bees and butterflies, adding movement and life to the garden. They also make lovely cut flowers and come in a range of pink, white, and orange shades.
4. Sunflowers
Sunflowers are iconic summer blooms known for their tall stems and bright yellow petals. You can plant them in May and still enjoy flowers by mid to late summer. Sunflowers grow quickly and prefer full sun and well-drained soil. They come in many sizes, from dwarf types for containers to giant varieties that tower over the garden. Birds love the seeds, and the flowers are excellent for attracting pollinators.
5. Nasturtiums
Nasturtiums are colorful, trailing or bushy plants with edible flowers and leaves. They do best in full sun to part shade and prefer poor soil, which helps produce more blooms. You can direct sow the seeds in May, and they’ll germinate quickly in warm soil. Their bright red, orange, and yellow flowers attract bees and hummingbirds. Nasturtiums also help deter certain insects and are often used as a companion plant.
6. Petunias
Petunias are a garden favorite, offering bright, trumpet-shaped flowers in many colors. They grow well from transplants or seed and bloom steadily through summer. These annuals do best in sunny locations with well-drained soil. Petunias are great in garden beds, hanging baskets, and containers. Regular deadheading helps them keep blooming, and some varieties are even fragrant.
7. Salvia
Salvia is a hardy, drought-tolerant plant that adds spikes of purple, blue, red, or pink to summer gardens. It thrives in sunny spots and grows well in average soil. Both annual and perennial types are available, but many gardeners plant annual salvia in May for summer color. Bees, butterflies, and hummingbirds love the nectar-rich blooms. Salvia is also deer-resistant, making it ideal for areas with wildlife pressure.
8. Calendula
Calendula, also known as pot marigold, is a cheerful flower that blooms in shades of yellow and orange. It prefers cooler weather but still does well when planted in May in most regions. Calendula grows quickly and can tolerate light frost if planted in cooler zones. The flowers are edible and often used in herbal remedies. This plant also attracts pollinators and repels some garden pests.
9. Verbena
Verbena is a sun-loving plant with small clusters of brightly colored flowers. It blooms throughout the summer and works well in containers, hanging baskets, or borders. Verbena prefers well-drained soil and benefits from occasional trimming to encourage new blooms. It is heat-tolerant and attracts butterflies. Many gardeners use it to fill gaps in beds where other flowers may struggle in the heat.
10. Celosia
Celosia is known for its unique, feathery or crested blooms that resemble flames or coral. These bold flowers come in red, orange, pink, and yellow shades and do well in warm weather. Celosia prefers full sun and moist, well-drained soil. It adds texture and height to garden beds and works well in containers too. The flowers are long-lasting and even hold their shape when dried.
11. Coreopsis
Coreopsis, sometimes called tickseed, is a low-maintenance flower with daisy-like blooms. It prefers full sun and grows well in average soil. Coreopsis blooms from early summer through fall and attracts butterflies. Some types are annuals, while others are perennials, but both can be planted in May for quick color. The bright yellow or red-and-yellow flowers bring warmth to any garden space.
12. Morning Glories
Morning glories are fast-growing vines with trumpet-shaped flowers that open in the morning sun. Planting seeds in May allows enough time for them to climb and bloom during the summer. They grow best in full sun with well-drained soil and will need a trellis or fence for support. Morning glories attract pollinators and come in shades of blue, purple, pink, and white. Be aware that the seeds are toxic if eaten.
13. Sweet Alyssum
Sweet alyssum is a low-growing plant with tiny, fragrant flowers that form a carpet of white, pink, or purple. It grows quickly and does well in full sun or partial shade. Alyssum is great for borders, hanging baskets, or filling in gaps between larger plants. It attracts beneficial insects and tolerates cooler nights. Regular watering helps keep it blooming through the heat of summer.
14. Impatiens
Impatiens are a top choice for shady gardens, offering soft, colorful blooms in pink, red, white, and purple. They do best in moist, well-drained soil and need regular watering, especially in warmer weather. You can start them from transplants or sow seeds indoors before moving them outside in May. Impatiens are perfect for containers, window boxes, and garden beds in low-light areas.
15. Snapdragons
Snapdragons are upright, spiky flowers that bloom in a rainbow of colors. While they prefer cooler weather, you can still plant them in May for early summer blooms, especially in regions with mild springs. Snapdragons grow best in full sun to partial shade with well-drained soil. Their unique flowers attract bees, and they make excellent cut flowers. Pinching back the stems can encourage bushier growth.
16. Portulaca (Moss Rose)
Portulaca is a heat-loving, drought-tolerant ground cover with vivid, rose-like blooms. It thrives in hot, dry conditions and poor soil, making it ideal for rock gardens or containers. The flowers close at night and open in full sun, showing off colors like pink, yellow, orange, and white. Portulaca grows quickly from seed or starts and spreads easily. It also attracts butterflies and bees.
17. Dianthus
Dianthus includes a variety of small, clove-scented flowers that bloom in pink, red, and white. They prefer full sun and well-drained soil and grow well in garden beds or containers. These low-growing plants are easy to care for and can be started in May for summer blooms. Some types are annuals, while others return each year. Deadheading helps them keep flowering throughout the season.
18. Bachelor’s Buttons (Cornflowers)
Bachelor’s buttons are hardy, old-fashioned flowers known for their bright blue color, though other shades are available. They grow easily from seed and do well in sunny spots with average soil. Plant them in May for blooms by early to mid-summer. These cheerful flowers attract bees and butterflies and also make excellent cut flowers. They can reseed themselves, returning in future seasons.
19. Gaillardia (Blanket Flower)
Gaillardia is a tough, drought-tolerant flower that brings rich, warm colors to the garden. It grows well in full sun and poor soil and is perfect for dry or sandy areas. Gaillardia blooms look like small sunbursts, with red, orange, and yellow tones. You can plant them in May for flowers by midsummer. They attract pollinators and require little care once established.
20. Rudbeckia (Black-Eyed Susan)
Rudbeckia, often called black-eyed Susan, is a sunny yellow flower with a dark center. These plants are tough, thriving in full sun and a variety of soils. Though often grown as perennials, some varieties bloom in their first year when planted in May. Rudbeckia blooms for weeks and is excellent for borders or wildflower gardens. It also draws bees and butterflies.
21. Gomphrena (Globe Amaranth)
Gomphrena features round, clover-like blooms in shades of pink, purple, red, and white. This heat-tolerant annual loves sunny spots and well-drained soil. You can start seeds in May for summer-long color. Gomphrena flowers are long-lasting and make good cut or dried flowers. They attract pollinators and add texture to garden beds and borders.
22. Lantana
Lantana is a tough plant that thrives in heat and drought once established. It has clusters of tiny flowers in mixed colors, like pink, orange, and yellow. Lantana blooms all summer and attracts bees, butterflies, and hummingbirds. It grows well in containers or beds and prefers full sun and well-drained soil. In warmer zones, it may even come back the next year.
23. Tithonia (Mexican Sunflower)
Tithonia is a tall, heat-loving annual that produces bold orange or red flowers. It thrives in full sun and poor soil and tolerates drought well. Plant seeds in May for blooms by midsummer. Tithonia attracts many pollinators, especially butterflies and bees. Its bright flowers also make great cut blooms, and the tall plants add height and drama to garden beds.
24. Cleome (Spider Flower)
Cleome is a tall, airy plant with spidery blooms in pink, white, or purple. It prefers full sun and can handle dry soil once established. Cleome grows quickly from seed and makes a bold statement in the garden. The flowers attract pollinators, and the plant’s height works well in the back of beds or borders. Be aware that cleome may self-seed in some areas.
25. Nicotiana (Flowering Tobacco)
Nicotiana produces tubular flowers that release a sweet fragrance in the evening. It does best in full sun to partial shade and prefers rich, moist soil. Planting seeds in May will give you blooms by midsummer. The flowers come in white, pink, red, and lime green and attract moths and hummingbirds. Nicotiana works well in flower beds or containers and adds scent to summer evenings.
26. Dusty Miller
Dusty miller is known for its soft, silver-gray foliage that adds contrast to flower beds. While it does produce small yellow blooms, it’s mostly grown for its leaves. Dusty miller prefers full sun and well-drained soil and can handle drought once established. It pairs well with brightly colored flowers and adds texture to garden designs. You can start it in May for summer and fall interest.
27. Zinnias
Zinnias are bright, cheerful flowers that thrive in full sun and warm temperatures. These annuals grow quickly from seed and bloom in just a few weeks, making them perfect for planting in May. Zinnias come in many colors and sizes, from short border plants to tall varieties for the back of the garden. They love well-drained soil and benefit from regular deadheading to keep the blooms coming. Butterflies are especially drawn to zinnias, which are great for pollinator gardens.
Keep Your Garden Blooming All Season
There is still time to grow a beautiful garden that shines through summer and into fall. You can take advantage of the warmer soil and longer days ahead by choosing the right plants for May. These flowers are easy to start now and offer lasting color, texture, and charm. Whether you love bold blooms, soft pastels, or something in between, you will find something here to suit your style and space. With just a bit of planning and care, your garden will stay lively and full of color for months to come.