Pros And Cons Of Growing Cosmos Bipinnatus

cosmos bipinnatus

When it comes to gardening, there are a lot of different plants that you can choose from. One option is Cosmos bipinnatus, which is also known as the Mexican aster. This plant has a variety of benefits and drawbacks that you should consider before deciding if it is the right choice for your garden.


A close up of a flower

1. Cosmos ‘Cosmic Purple’ is the most common Cosmos bipinnatus because it has a compact growth habit and effectively produces flowers.

2. Cosmos bipinnatus tolerates poor soil conditions, as long as the soil drains well. This makes it a versatile plant that can be suited to many areas of the garden, even those with low fertility or difficult growing conditions.

3. Cosmos bipinnatus flower attracts a lot of pollinators due to its showy petals and the honey-like fragrance manufactured by their nectar glands inside the inner corona. This means not only will your plants produce more flowers for you during the blooming season, but also so will other plants in its vicinity!

4. They’re great for container gardens too! In fact, since they grow to be only about 8 inches tall, they’re perfect for window boxes and hanging baskets.

5. They are deer-resistant! This means that you can plant them in areas where deer always seem to cause a problem with other plants.

6. Cosmos bipinnatus is a dependable performer in the garden, which means it will come back every year and perform well again next season.


A close up of a flower

1. They have narrow petals, so if pollinators or small children get too close to their base, there is a chance they might damage the petals by pulling on them or squeezing them too tightly.

2. The flowers tend to sway when in windy conditions because of their light weight and long stems—so they may not be the best choice in a windy, exposed location.

3. They are annuals, so they must live through cold winters in order to return and flower again next spring. If you’re located in an area where frost occurs during the winter and you want your Cosmos to grow and flower year after year, we recommend starting new plants every spring or growing them as annual bedding plants (like flowers commonly seen in containers at grocery stores).

4. To achieve fuller blooms, pinch off all but the last set of leaves on each stem about 2 inches from the soil line when you first plant them (and even before that if it’s still early enough for them to emerge). This will redirect energy into branching stems, creating more blooms.

5. It’s important to realize that the flowers will only grow and form petals and leave if they receive enough sunlight, so place them in full sun for the greatest effect. If you find those areas don’t get enough direct sunlight, you can supplement with a grow light during winter months or when it gets too cold outside to allow them to receive adequate sunlight.

6. Even though Cosmos bipinnatus plant is deer-resistant, do watch out for slugs! They’re known to eat Cosmos ‘Cosmic Purple’, as well as other Cosmos varieties like ‘Purity’ and ‘Tequila’. If you notice holes in the leaves of your plants and aren’t sure what could be causing it, make sure to check carefully under the leaves for slimy trails. This might be a sign of slugs!


Growing cosmos bipinnatus plants can be a fun and rewarding experience. They are simple to care for, come in a variety of colors, and have many uses outside the garden. But before you plant these flowers this year, make sure that they will thrive where you live with our guide to growing them successfully!

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