How To Grow And Care For Osteospermum (African Daisy)

This detailed Grow Guide contains everything you need to know about growing Osteospermum.

An excellent plant to use for long-lasting display, colourful blooms in wide range of colours from late spring, during the summer and into autumn is Osteospermum, commonly called the Cape Daisy or African Daisy, which make them a perfect garden plant. Originally from southern Africa, the African continent in general, and parts of the Arabian Peninsula where they grow in veldts and grasslands. A large variety of plants were introduced to Europe in the 19th Century and cultivated there ever since. African Daisy flowers face the sun by nature, so they are phototropic. The flowers close up when the sky is heavily clouded and at night. 

Osteospermums are shrubby evergreen perennials, and they’re related to the annuals, the Dimorphothecas (Cape Marigold), which are often sold under the name of Osteospermums. So, you have to be careful when you buy them that you actually get the right variety

Osteospermums are ideal for front-of-border planting in milder regions of the country, or in flower beds for the summer. African Daisies come in several colours and cultivars, and the flowers are attractive to pollinators due to the vibrant colours. They can be grown successfully in containers too!

There are a few types of osteospermum which are tender or half-hardy, especially in cooler climates. You can grow these varieties as annuals or move them indoors in autumn to overwinter.

Osteospermum are either considered perennials or annuals in the United Kingdom depending on how well they can survive a British winter and/or can be grown. Two Hardy types of Osteospermum can be perennials in the U.K. these include “Osteospermum ecklonis” and “Osteospermum jucundum”, these two varieties have been known to survive temperatures as low as -10°C (14°F)

You can also find some African Daisy plants  that are drought resistant such as the “Osteospermum jucundum”

Great osteospermum varieties to grow

Osteospermum Purple Sun

Your garden will be flooded with fiery color from Osteospermum ‘Purple Sun”s daisy-like flowers with the vivid Lilac and Apricot. Their colors resemble the hues of a summer sunset twilight sky.

From spring through autumn, the compact, uniform plants make for wonderful border plants, mass plantings, and other container arrangements. Their abundant heads of bloom will overwhelm your containers more than traditional varieties, and attract bees and butterflies to your flower beds. Will reach a height of 30cm and a spread of 50cm.

Osteospermum Serenity Red

In addition to the dark dark red flowers of ‘Serenity Red’ almost feeling velvety, they are each encrusted with dark red veining that leads into the center of the floret. At the beginning of June, the flowers began opening, and by the end of August, they had almost covered the plants with blooms. They were surrounded by long, oval leaves, which also showed off the impressive blossoms Will have a height of 25cm and a spread of 35cm.

Osteospermum “Sunny Philip”

In contrast, the blooms of Osteospermum ‘Sunny Philip’ are shaped like spatulas with flat, white petals that fold midway to reveal purple undersides. A mixed, sunny border is the perfect spot to grow this plant, along with being beautiful as a cut flower. Will grow to 60cm tall and 60cm wide.

Osteospermum “3D Yellow”

The head of ‘3D Yellow’ is covered with pale yellow flowers that resemble mini chrysanthemums. Petal pom-poms cover the flower heads. Despite the occasional dull day, the flowers don’t close and the mid-green foliage adds a splash of color in a shady spot. A great idea would be to plant it in a pot and place it on the patio. The majestic plants started blooming in July, and by August, they were covered with blooms that lasted well into October. Will reach a height of 30cm and a spread of 40cm.

Osteospermums Care

The African Daisy looks great in containers, beds or in borders the spread of some varieties will make a stunning ground cover display. You can easily care for Osteospermums. Generally they do not require much maintenance once established and provide a cheerful and self-sustaining addition to the garden.

Many shrub species grow to one metre in height; however, others are much smaller, like Osteospermum ‘Cannington Roy’ or Osteospermum ‘Snow Pixie,’ reaching only 15 centimetres in height

From its leaves to its roots, Osteospermum has a variety of characteristics. It depends on the species or cultivar whether the leaves are lanceolate or inoculated, toothed or entire. Furthermore, plants can produce leaves that are shaped differently by species, such as Osteospermum ecklonis! Hardy varieties are generally thought to have toothed leaves. This type of plant produces clumps of leaves rather than leaves that grow upright.

Approximately 70 species of the African Daisy are known, with more than 900 varieties. It is not just the ray florets that distinguish these plants, but also their central disks. Sometimes these disk centrals set off the rays in a stunning way or sometimes they are of deep metallic colours and are attractive on their own. Among some varieties, there are bicolored disks; and, in others, there are radiating rays.

How to start Osteospermum from seed? 

African Daisies will germinate at a temperature of 18-20°C (64-68°F) so they are best kept in a heated propagator.  They will take about 10 to 14 days to germinate.
Get a seed tray and fill it with soil leaving about a 1cm from the top of the tray.
Add a seed to each tray module from your choice of packets of seeds
Now add some more compost enough just to cover the seeds
Water well and place them into a heated propagator., remember to transplant them into larger pots as they grow, then harden them off for a couple of weeks before finally planting them outside after the risk of frosts has passed.

How To Plant Osteopermum

After any chance of frost has passed, Osteospermum can be planted in May. Make sure the soil is free draining in a sunny location. When plants are bought, they should be planted out as soon as possible after purchase. However if there there is still a chance of frost then plant them into larger pots, this will allow your African Daisies to keep on growing without becoming rootbound. Before planting, mix an organic fertiliser or soil improver. Create a hole twice the size of the root ball. Put the plant at the same level as in the pot so that it is level to the soil. Firm in, backfill, and water well.

To plant plants you have grown from cuttings, dig some organic fertilizer or soil improver into the soil. Prepare the holes by digging 10-15 cm holes apart (4-6 inches) depending on the mature size of your variety. You will need to remove the plants from their pots, untangle their roots, and place them in the holes that you have prepared. The plants should be firm in place by gently backfilling the holes and depressing the roots to remove any air pockets around them. Make sure to water well any newly planted plants.

How much light does your Osteospermum (African Daisy) need?

Depending on the season, Osteospermum prefers a sunny position either in a pot on a nice sunny patio or in the border. The flowers will bloom best if the plants are in full sun, though they can tolerate partial shade.

How much water do Osteospermum Plants need?

Dry conditions are well tolerated by these plants. The first two weeks after planting, they need to be well watered. During periods of dry weather, they may only need to be watered once a week once established. If container grown plants are allowed to completely dry out, they may drop buds and not flower. In periods of drought they will not produce any flower buds.

What is the ideal soil type for your Osteospermum Plants?

For best results, amend heavy soil with plenty of grit before planting, because these plants prefer free draining soil. Garden Soil improvement or organic compost will work well if you have poor soil. To prevent the roots from becoming soggy, any pot for these plants should have good soil drainage. The African Daisy loves well draining soil, adding sand or grit can give you well drained soil.

How often should you apply fertiliser to your Osteospermum (African Daisy Plant)?

When your osteospermum is growing, you should feed it every two weeks to encourage flowering. If you’re growing them in containers then this is particularly important.

A good Tomato feed fertiliser works well when feeding your Osteospermum Plant

Taking Osteospermum cuttings and Osteospermum Propagation

In case your plants don’t survive the winter, it’s a good idea to take softwood cuttings.

Ideally, you should do this late summer or the beginning of autumn.

You can use any size pot to grow on your cutting with a good compost mix, before planting your cuttings. Cut a 5-7cm stem just below the leaf node (this is where the new roots will form) with no flowers on it. Then remove nearly all the leaves on it, leave about a third of the leaves on it. It’s a good idea to dip the bottom of the stem in a rooting hormone, if you don’t have any rooting hormone then you can use cinnamon instead.
Remember to water your cuttings and then place them in a warm location out of direct sunlight, they require warmth to establish new roots.

Keep the cuttings from drying out and don’t let them shrivel up. Ensure all dying or dead matter is removed regularly. The plants should be potted into 9 cm pots once they have roots, if you were growing several cuttings in a pot. Growing tips should be pinched out to promote bushier growth at this stage. Make sure they’re kept in a sheltered, frost-free spot, such as a greenhouse. Don’t forget to harden off your plants for a couple of weeks before planting them out in their final position after the last frosts around May.

When to prune Osteospermum?

Early spring or after the blooms in autumn is the best time to cut back hardy Osteospermums. You need to water your Osteospermums regularly to keep them healthy, try to avoid allowing them to dry out. It is beneficial to cut back Osteospermums to around 3 inches in height before new growth begins in early spring for hardier varieties. If the old foliage is removed, the plant will be encouraged to grow new growth.

How to encourage your Osteospermum to flower more? How to deadhead Osteospermum?

It’s really simple to do, once you see a wilted flower (has started to dry up) then just get a good sharp pair of garden pruners and go down the stem to where the next level of set leaves are and cut just above them or you can go down to where you see the newest growth is on the stem and cut above it. This prevents the flowers from going to seed and causes the plant to produce new flowers.
Have a look at the below video to give you a better idea.

Overwintering 

Generally thought of as annuals, Osteospermum species are actually half-hardy perennials that can be overwintered in areas where frost cannot reach as established plants or as cuttings rooted pots or seed trays. 

Osteospermum problems

 When it is in good health and not stressed, this ‘bone-hard’ plant is relatively free from diseases and pests.

Two fungal diseases, grey mold and downy mildew, can affect Osteospermum in high humidity. Both cases require immediate cutting off of the affected plant areas. Reducing humidification and increasing air circulation can help plants grow indoors. If it’s growing outdoors make sure that it has plenty of circulation and other plants are not overgrowing it.

Despite the fact that fungicides cannot control downy mildew, you can treat grey mould with thiophanate methyl after cutting off the affected section.

The plant may also be affected by insects, namely aphids. Their rapid growth and amount of damage makes them one of the most destructive pests. Apply an Orthene solution at a one percent strength to the infestation and the surrounding foliage.