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Growing Clematis – Great Vine for Mailboxes

These tips for growing clematis will help you give this vining plant a home in your back yard.

Last spring, I repurposed an old mailbox into a place for my garden tool storage. I planted a few different plants around the base, but I was never happy with the look of it.

I decided I wanted a climbing plant to cover the post and grow up around the mailbox itself to decorate it.

I wanted a perennial that would come back year after year and chose clematis because it is such a good climber.

Clematis is a perennial and some varieties will get really large, so it is important to keep this in mind, particularly if you plan on growing it in a pot.

Like mandevilla vine, some types of clematis will grow 15 feet or more, so may need regular pruning to keep it in check.

How to Grow Clematis - The perfect plant for a mail box.

Growing Clematis plants is easy with these few steps.

Growing clematis plants is not difficult. The flowers are large and showy and the plant does a good job of covering trellises or posts in no time at all. 

They are one of the few blue flowers that I have in my garden. (well sort of a purple blue, but with blue flowers, you can’t be choosy!) Here are some growing tips for clematis.

Sunlight and water needs for clematis

Clematis grows best when it gets 3-6 hours of sunlight. Ideally, place clematis so that the top of the plant grows in sun and have the root zone be shaded by other plants.

Water when the top of inch of the soil is dry.  They need about an inch a week.

Soil needs and fertilization requirements for clematis

Choose  a well draining soil. Adding compost at planting time will add extra nourishment to your soil, particularly if it has too much clay. 

Feed once a month during the growing season with a well balanced fertilizer.

Clematis vine

Size of clematis and blooming time

Growth is normally 3-15 feet tall for a mature plant.  Prune to keep it a manageable size.

Clematis blooms from early summer until fall.

To promote re-flowering a second time during the growing season, the vine can be cut by one-half after the main bloom period.

Clematis varieties can bloom on old wood, both old and new wood, and new wood only.  Pruning needs to done depending on which variety you have. 

Mine blooms on old wood, so it should be pruned as soon as it flowers. Those the bloom on new wood only, just remove growth from the previous year. 

And if it blooms on both old and new, prune once it gets crowded.

Does clematis need support?

Provide the clematis with good support. Once the vine starts growing, gently tie them onto the support using twine or yarn.

Proper vertical support will allow your clematis to become bushier and taller, leading to more foliage and a greater amount of flowering.

A wooden garden obelisk is a good choice for support. It is functional and decorative as well.

Clematis also does a good job of hiding a chain link fence is planted near one.

Problems for clematis plants

Clematis is susceptible to fungi that can cause the vine to suddenly wilt and turn brown or black.

Carefully prune out all diseased tissue and disinfect your pruners with a bleach solution.

Be on the lookout for thrips, aphids, caterpillars and whiteflies, which can all infest clematis.

Hardiness zones for clematis

The plant is quite hardy.  Mine will take temps to -30 degrees Fahrenheit. It is cold hardy in zones 4-9.

 This is my beauty.  Can’t wait to plant it near the mail box. Hopefully this week!

clematis close up of flowers

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Would you like a reminder of this post for care tips for clematis? Just pin this image to one of your gardening boards on Pinterest so that you can easily find it later.

Blue clematis flowers with words Tips for Growing Clematis.

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greta vines

Friday 15th of January 2021

Does the clematis need wood to climb on? I have a new plastic mailbox and I want to plant something around it. I cut a couple trees and will wait until spring to see how much sun I have.

Carol Speake

Friday 15th of January 2021

I had a plastic trellis once and it climbed on that, so I don't think it needs wood.

Donna Paskett

Sunday 23rd of July 2017

Do all clematis bloom all summer? Mine only blooms in the spring and early summer. I would like it to bloom longer. So do i need a different one?


Sunday 23rd of July 2017

Hi Donna. It depends on the variety. Most are early bloomers, but you can encourage a second bloom time with careful pruning of the plant. Carol

Donna Paskett

Sunday 23rd of July 2017

do all clematis bloom all year? Mine only blooms in the spring and early summer.


Sunday 3rd of May 2015

If my mailbox and post-surround are plastic (fits over a wooden post, but the wood is not exposed), will clematis not grow and thrive?

If it will work, do I provide a trellis right away, or will supporting clematis by tying it as it grows to the mailbox suffice instead of a trellis?

The mailbox is on the west side of the property and will get sun from 11-12 on then all afternoon. Is that too much? Is there a concern for overheating the roots?


Sunday 3rd of May 2015

Hi Kevin,

I have some clematis climbing on a plastic trellis right now. I don't think that will matter. It is easier to get it to climb with a trellis but it will attach and climb around most anything. It's pretty persistent in this regard.

Mine is sitting in the sun right now, but it does get burned here in NC from too much sun. I don't think the roots will suffer, but the leaves may from that much sun. Carol


Saturday 17th of January 2015

I have grown clematis for a couple years and love them. I have been looking for this exact color as you have pictured and have had no luck in finding this shade. Do you know the name of this particular variety? I'd appreciate any info on this. Thank you.



Saturday 17th of January 2015

Hi Carol. This variety is called "ice blue". I got it at a local walmart about 3 years ago. Carol

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