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Homepage » Gardening » Flowers That Start With The Letter

Published: Mar 4, 2023 · This post may contain affiliate links. As an Amazon affiliate, I may earn a small commission from visited links at no additional cost to you. · Leave a Comment

Flowers That Start With The Letter O

These flowers that start with O are bright spots to add to any landscaping design to add beauty throughout your yard to last through the seasons! From the beautiful orchid to the distinctive look of oxalis, you will surely find flowers to delight you with gorgeous blooms!

Flowers That Begin With The Letter O
Read Next
  • 10 Outstanding Flowers That Begin With The Letter O
  • Orchids
  • Ohio Spiderwort
  • Oxalis
  • Obedient Plant
  • Oenothera
  • Oleander Plant
  • Oriental Lily
  • Oriental Poppy
  • Osteospermum
  • Oyster Plant

10 Outstanding Flowers That Begin With The Letter O

Orchids

Scientific Name: Orchidaceae

Type Of Flower: Herbaceous Perennial

When Do They Bloom? Varies Depending On The Species

Orchids are well-known plants that can be grown both indoors and outside. It is a great plant for beginners because it is low-maintenance and straightforward. There are many species of orchid plants; their flowers range in color from white, red, orange, yellow, green, purple, and pink! A full rainbow of colors to choose from!

These plants grow all over the world and are native to North America, South America, Central America, Europe, Asia, Africa, and Australia! They stand between one and three feet in height and grow best when planted in partial sunlight. Orchids don’t require direct sun, which is why they can grow easily indoors.

Quick Fact: There are more than 30,000 different species of orchids!

Ohio Spiderwort

Scientific Name: Tradescantia ohioensis

Type Of Flower: Herbaceous Perennial

When Do They Bloom? Late Spring & Mid-Summer

Ohio spiderwort is a plant that produces small blue flowers that grow in clumps atop its grass-like stems. Its flowers consist of three small petals with bright yellow stamens in the center.

These plants are considered aggressive wildflowers due to their self-seeding abilities, which can often take over if they aren’t managed. Pull newly sprouted flowers early on to reduce the chances of them taking over your garden. They thrive best in full or partial sunlight and well-drained soil.

Quick Fact: Ohio spiderwort flowers bloom early in the morning and close during the afternoon when it is hot!

Oxalis

Oxalis

Scientific Name: Oxalis triangularis

Type Of Flower: Perennial

When Do They Bloom? Spring, Fall, & Winter

Oxalis is a unique-looking plant. It has deep purple leaves that grow in groups of three. During its blooming season, it will produce small white, pink, or purple flowers that contrast with its purple foliage.

Oxalis is a low-maintenance plant which makes it great for new gardeners. It grows at a moderate pace, often maturing within ten (10) weeks. This plant is often grown indoors as a houseplant but must be grown in an area that relieves ample sunlight.

Quick Fact: Oxalis is also called wood sorrel, false shamrock, love plant, and purple shamrock!

Obedient Plant

Scientific Name: Physotegia virginiana

Type Of Flower: Perennial

When Do They Bloom? Summer & Fall

An obedient plant is a bold plant that grows up to four feet tall with long purple, white, or pink flowers that sprout on the top of its long narrow stems. This plant is a quick grower that can easily take over in gardens that supply ideal growing conditions.

Native to North America, the obedient plant is a member of the mint family. It thrives in gardens with access to full sunlight and loves rich and acidic soil. Be sure not to over-water your obedient plant because it only requires watering once or twice per week. Too much water can cause fungus to form in its roots.

Quick Fact: Obedient plant is also called false dragonhead!

Oenothera

Scientific Name: Oenothera biennis

Type Of Flower: Herbaceous Biennial

When Do They Bloom? Summer & Fall

Oenothera is truly bold and beautiful with its lovely yellow blooms. This self-seeding plant is fragrant and quite the showstopper, but it can quickly take over your garden if it is given a chance! Be sure to keep this plant from spreading by taking preventative measures!

This plant loves moist soil, but be careful that the soil isn’t too moist because it is prone to root rot and fungal diseases. Plant Oenothera in an area where it can receive six to eight hours of daily sun.

Quick Fact: Oenothera is also called evening primrose, fever plant, and cure-all plant!

Oleander Plant

Oleander Plant

Scientific Name: Nerium oleander

Type Of Flower: Shrub

When Do They Bloom? Spring & Summer

Oleander is a beautiful plant that produces elegant white, pink, red, or yellow flowers. The flowers are fragrant and quite showy, but beware that they are toxic for humans and pets! Plant oleander away from areas where pets or children play.

Oleander grows best in alkaline soil and full sun! It is a great plant for beginners because it needs minimal care once it is established. This plant will grow approximately two feet per year until it reaches between 15 to 20 feet tall.

Quick Fact: Oleander is also called Nerium, Jericho rose, and rose laurel!

Oriental Lily

Scientific Name: Oriental liliums

Type Of Flower: Perennial

When Do They Bloom? Late Summer & Early Fall

The Oriental Lily is a hybrid plant that produces sought-after flowers that are either white, red, or pink with a bold yellow stamen in its center. These flowers are fragrant, which draws people to them, and they last a while when cut, which makes them great for bouquets and vases.

These flowers are grown in acidic soil because alkaline soil will hinder their growth. Place them in full or partial sunlight and watch their magic take over as they produce their vibrant blooms!

Quick Fact: The Oriental Lily is also called the flat-faced stargazer!

Oriental Poppy

Oriental Poppy

Scientific Name: Papaver orientale

Type Of Flower: Herbaceous Perennial

When Do They Bloom? Spring & Summer

The oriental poppy plant is a great addition to gardens that want a lovely pop of color. Its flowers are wonderful shades of red, orange, pink, purple, and white. The petals of the oriental poppy are thin and wispy and grow rapidly and die quickly.

Be sure to grow these plants in full sunlight to help them reach their full potential. Do not overwater your oriental poppy plants because they can’t survive in wet soil and are prone to root rot.

Quick Fact: The Oriental poppy is toxic to humans, dogs, and cats!

Osteospermum

Scientific Name: Osteospermum spp.

Type Of Flower: Perennial & Annual

When Do They Bloom? Spring, Summer, & Fall

Osteospermum plants produce round flowers with many long petals that range in color from white, yellow, orange, pink, and purple. They have a circular center that glimmers in the sunlight and tall stems that have deep green foliage.

These plants love fully sunlit gardens but can be planted in pots, window boxes, or trays that receive partial sun. Osteospermum is a drought-tolerant plant later on in its life but requires regular watering to help it begin blooming.

Quick Fact: Osteospermum is also called the African daisy and the cape daisy!

Oyster Plant

Scientific Name: Tradescantia spathacea

Type Of Flower: Herbaceous Perennial

When Do They Bloom? Varies By Location

Oyster plants are mostly known for being houseplants, but they can also be planted outside in gardens, pots, or window boxes. These compact plants are wildly unique, with long green and purple leaves and pink or white flowers.

These plants are great for almost anyone who wants a fast-growing, easy-to-care-for plant. Oyster plants love indirect sunlight and acidic soil. If you plan on planting this plant outdoors, be sure it doesn’t get full direct sun, or else it can dry out.

Quick Fact: Oyster plants are toxic to people and animals.

More Great Articles To Read

  • Flowers That Start With The Letter Z
  • Flowers That Start With The Letter Y
  • Flowers That Start With The Letter V
  • Flowers That Start With The Letter X

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