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How Big Do Gardenias Get?

When I first was planting some gardenias in my garden, I wasn’t sure how big they would get. So, after doing a lot of gardening with them and doing some research, I thought I’d write this helpful article to explain it. Also, I  give some useful information about gardenias, so let’s go!

Gardenias grow to full size of 2 to 8 feet (60cm to 240cm) tall. Smaller varieties grow to 2 feet tall (60cm). Larger varieties grow up to 8 feet tall (2.4m). Their width is equal to their height. However, most people trim them into interesting shapes or as a simple hedge.

There are many varieties of gardenias. Some are better than others, so below, we’ll discuss the best gardenia varieties with a helpful table as well as how fast they grow, and some basic care reminders.

Gardenia has many beautiful varieties.

There are many varieties of gardenias that can be good based on what hardiness zone you plan to plant them in. The table below shows how big the popular Gardenia varieties will get when fully grown.

Popular Varieties Hardiness Zones Height Spread Sun
Gardenia thunbergia 10 to 12 5 to 16 inches (13 to 40cm) 4 to 10 inches (10cm to 25cm) Partial shade
August Beauty Gardenia 8 to 11 4 to 5 inches (13 to 10cm) 8cm Full sun to partial shade
Gardenia Radicans 7b to 9 1 to 2 inches (2.5 to 5cm) 3 to 4 inches (8cm to 10cm) Full sun to partial shade
Nanu or Na’u 10 3 to 20 inches (8 to 50cm) 2 to 6 inches (5cm to 15cm) Full sun
Gardenia Jasminoides 8 to 11 3 to 7 inches (8 to 18cm) 5 to 6 inches (13cm to 15cm) Partial shade
Aimee Yoshioka 8 to 11 5 to 8 inches (13 to 20cm) 4 to 7 inches (10cm to 18cm) Full sun to partial shade
Belmont Gardenia 7 to 9 4 to 8 inches (10 to 20cm) 3 to 6 inches (8cm to 15cm) Full sun to partial shade
Fortuniana Gardenia 8 to 10 4 to 8 inches (10 to 20cm) 4 to 8 inches (10cm to 20cm) Full sun to partial shade

So, regardless of what space you are growing your Gardenias in, you can find on that will fit. A ground cover one, a mid-sized one, or a very tall one. Very tall ones you should plant in the protection from wind, not out in the open. That way, they won’t be susceptible to being damaged by the wind.

Gardenias hate wet feet. This leads to root rot. This is where the roots break down because there is too much water. So, the soil needs to be free draining. If you are concerned about the draining of your soil, you can grow them in pots. Another option we recommend is digging a trench.

Mix the dirt you pulled out with pine bark, sometimes called pine bark soil conditioner. This will make the soil more free draining. You should then mound them up 3-4 inches (8 to 10cm) above ground level. Don’t over mulch. Don’t get any mulch up around the stems of them.

Plant them in a sunny place.

They should be planted in full sun to partial shade. Gardenias prefer full sun. The more extreme zones give them a bit too much sunlight, which can dry them out. Therefore, you should err on the side of planting them in partial shade in hotter states such as California or Texas.

Gardenias prefer moist soil. The ground can dry out quite quickly in hotter climates. This is a crucial reason why people use mulch. Mulch provides a barrier between the heat of the sun and the surface of the soil. This stops the ground from drying out. You should use mulch on your gardenias. They need more water than cactus or aloe vera type plants.

Varieties differ in how much water and sunlight they need to grow optimally. You should check the details of the specific variety. Regardless they keep their foliage year-round. They are also fragrant and have beautiful flowers, so you should find a variety that suits your region best.

When growing gardenias, you should consider sunlight, the wind, and soil drainage. If you are growing gardenias in pots, they should have partial shade. This is because the water in a container will dry out quickly in direct sunlight, and you will have to water them more regularly. We previously covered that Gardenias need free-draining soil.

For Gardenias that you are planting directly into the soil, you should give them more of less sun depending on what hardiness zone you live in. If you live in a hardiness zone which is on the high end, you should give them less sun. This is because the full sun can be too hot and dry out the plant. For colder hardiness zones, you can plant them in full sun without having them dry out. The more sunlight they get, the more nutrients they produce so, you should maximize the amount of sun they can get without drying them out.

Smaller varieties that grow low to the ground can withstand lots of wind. But, taller varieties should not be planted without cover from the wind, such as a fence, other trees, or a building. Stong wind can strip them of their leaves, and break off branches. This will cause them to have a much harder time growing to full size and producing as many flowers.

Under ideal conditions, the growth rate is faster.

Gardenias have an average growth rate when compared with other plants. There are many varieties. The larger the plant, the larger the flowers. Some grow large like a medium-size tree, whereas others hug the ground and have a creeping growth habit. Therefore, how long until they are fully grown can differ a lot.

Environmental factors will also influence their growth rate. If they have the optimum sunlight, water, and protection from the wind, they will grow optimally fast. Gardenias will produce flowers are 2-3 years on average, but depends on the variety. Some have been bred specifically to flower faster.

Gardenias are perennial. This is a scientific term which means that refers to plants that grow for more than two years. So, once it produces it’s flowers and autumn begins, it will keep its’ leaves. It also means that each year your Gardenia will produce flowers. This makes gardenias a low maintenance plant that is good to have in the garden. This is because they will continue to provide fragrant flowers year on year.

They are also versatile, where they can be used as a stand-alone tree, for hedges, or as low ground cover.

Conclusion

In conclusion, Gardenias grow to a full size between 2 to 8 feet (60cm to 240cm) tall. This is based on the specific variety you choose. Gardenias are known for their very fragrant and beautiful flowers. They are also perennial, meaning they produce flowers year after year. They take 2-3 years to begin producing flowers for most varieties.

They prefer free-draining soil that is kept moist and as much sun as they can tolerate without drying out. This is dependent on the hardiness zone in which you live. Hotter zones should be given less sunlight, while more temperate zones should be given more.