Planting dahlias: scary or simple?

Dahlias. They’re everywhere. Since Floret rocketed them to popularity over the last decade, you can hardly open up the Internet without seeing a dahlia somewhere. And for good reason! They are beautiful, come in a wide range of shapes and colors, and hold up super well in floral arrangements.

But that whole tuber thing…what is that about? What the heck am I supposed to do with that wrinkly little potato-like root? We’re diving into all things dahlias in this post, and hopefully you will leave feeling confident about growing the beautiful blooms in your garden.

Where to buy dahlias

Before you can plant dahlias, you need to find them! Here are a few of my favorite places to source dahlia tubers.

• Local flower farmers. My favorite place to buy dahlia tubers is from my friends at J&J Flower Co. Buying from friends and fellow farmers feels wonderful, plus I love their style so much, everything I buy is a sure thing! Whatever I don’t get from J&J I usually pick up from Swan Island Dahlias, also local. Search “dahlia growers” in your area!
• Etsy. In years past, I have found tubers from various sellers on Etsy and had great success! Especially for those hard to find varieties. This still puts money in the pockets of the little guys.
• Online sellers. When all else fails, hit the bigger companies. This year I ordered a couple speciality tubers from Eden Brothers. I will keep you posted on how they turn out! They have a super wide selection and great photos.

What is a dahlia tuber?

A dahlia tuber is literally the root of the dahlia plant, and is used to grow the beautiful famous flowers. Instead of a seed, you plant a chunk of the root system- or tuber- and this guarantees that the flowers look exactly like the parent plant whom the root was taken from. The clincher is, each tuber must have an “eye,” similar to a potato, so that it will produce a plant. If your tuber doesn’t have an eye, nothing will come of it.

Different varieties of dahlias will produce a wide variety of shapes and sizes of tuber clusters, but most look somewhat similar. And, the beauty of tubers is that they will increase in number each year and you can divide them for more dahlia plants!

How many dahlias do I need?

If you are just getting started, going with just a few tubers isn’t a terrible idea. I think I bought 6 my first year, and it was a perfect way to whet my appetite without too much of an investment. Tubers have gotten expensive, so it’s not a bad idea to make sure you know what you are doing before you spend all your hard-earned money.

In years past, I’ve planted up to 65 tubers in my garden. For a hobby gardener like myself, this was simply too many. I would recommend anywhere from 10-12 for most people. You can make sure you get enough variety, without out taking up too much space or requiring a second mortgage just for tubers.

Where do I plant my dahlias?

There are a variety of places you can plant your dahlias. Here are a few options:

• Flower beds/landscaping. I have never chosen to plant my dahlias in my landscaping simply because I typically dig them up in the Fall to store over Winter, and don’t want to disturb the other plants and soil in my flower beds. But, I know lots of folks who do and it’s a perfectly good option.
• Vegetable garden. This is how I’ve enjoyed dahlias in my gardens over the years. At our old house I had a designated dahlia section each year, and tried the same thing the first year at our homestead. But now, I love to incorporate dahlias all over the Potager garden, tucking them in next to my roses and alongside other perennials in the beds.
  
  Either way works! It’s so fun to see them en masse, and it’s also so lovely to have them peeking out from in between other plants.
• Dahlia patch. I know more than a few folks who love dahlias so much they put in an entire “patch” or garden space just for the beautiful blooms. If you are growing a larger volume, or enjoy photographing large quantities of the blooms all together, this method is for you!
  
  I drove by J&J Flower Co.’s dahlia patch for months before I finally figured out who they were. I just knew I had to be friends with whoever loved dahlias that much!
• Containers. Dahlias can look amazing planted in a large barrel style planter with a few other blooms. This is a perfect method for a newbie! Or city dweller. It also makes them easy to remove in the Fall.

How to plant dahlias

Now that you get the whole tuber thing and you’ve purchased the type and quantity you need, it’s time to get those babies in the ground! Here’s how to plant your dahlias for the best results:

• After the last frost (usually the first week of May), dig a hole 4-6 inches deep and wide enough for your tuber/tuber cluster.
• Put the tuber in the hole with the eye (or maybe little sprout at this point) facing up.
• Cover with soil. Dahlias should be planted 12-18 inches apart, typically.
• Don’t water your dahlias until little green shoots poke up through the soil. But make sure they have a water source, as they’ll need a few good soakings a week once they begin to grow.
• Pinch off the center of the plant as they begin to grow. This is HARD! But will mean more flowers all summer long.

Do dahlias come back every year?

Dahlias can be grown as an annual or perennial.

• Some people dig them religiously every year, store them over the winter in peat moss or vermiculite, divide and replant them each Spring.
• Others simply leave them in the soil over winter, heavily mulch to protect from frost and divide every few years for plant health.

Honestly, it really depends on your climate. I have tried both methods and had varying degrees of success. It all depends on personal preference and your location. There’s really no wrong way to grow a dahlia!

When will my dahlias bloom?

One of the best parts of growing dahlias is the long growing season. Depending on where you live, typically dahlias begin to bloom in July and will last right up until your last frost. This means that some years I have had dahlias all the way into November. Talk about bang for your buck!

As long as you keep them dead-headed (cutting away the spent blooms), your plants will keep producing until the frost takes them out.

Should I plant dahlias in the sun or shade?

Sun. Dahlias are sun-lovers and want to be in the warm rays at least 6-8 hours a day.

Dahlias from seed?

Tubers aren’t the only way to grow dahlia blooms, there are lots of amazing dahlia varieties which can be grown from seed. BUT, the thing to know about growing dahlias from seed is that they are kind of a different animal. Dahlias from seed usually have a yellow center, with only one layer of petals coming out of it. They are also a bit wild, meaning you never really know what you are going to get.

If you grow a dahlia from seed that you really love, you can save the tuber and have that bloom again the next year. Floret has done a ton of work breeding dahlias and has lots of good info on her website and in her books.

Dividing dahlia tubers

So you bought a bunch of tubers that you absolutely love, you dug them in the Fall, successfully stored them over Winter and now you’ve got big giant bundles of tubers. Do you just stick those beasts in the ground!? Well, you can. But the best way to increase your dahlia patch without spending a penny, is to divide those tubers.

Here’s how to divide your tuber clusters for more dahlia plants:

• Find the eye. Like a potato, each chunk of tuber needs an eye in order to grow a plant. This can be really tricky to find early on, but if you wait until just before planting to divide, often times the eyes have turned into a sprout and are easier to see.
• Make the cut. There are so many different ideas on where to cut the dahlia tuber chunks apart, but I have found that as long as you have an eye, it really doesn’t matter all too much. Just make the cut! Don’t be afraid.
• Plant ’em up! Put those brand new dahlia babies in the ground and wait with bated breath for those first green sprouts. Remember! Don’t water until they begin to sprout and leaf out.

Books on dahlias

If you are anything like me, there’s nothing better than a good book. Here are a few of my favorite books on dahlias.

• Discovering Dahlias. Erin is the queen of dahlias and this book is flawless. It contains a photographic index of basically every variety you could dream of, and every year I use it as a reference for one thing or another. A must have for your gardening library!
• The Joy of Dahlias. This book is actually all about Dutch dahlias and the industry over there, but I found it absolutely fascinating. It actually reads more like a blog than a gardening book, fun and casual and filled with personal anecdotes. Worth a read!

Are you a dahlia lover?

Leave a comment below with your favorite dahlia varieties, what you’re planting this year, your favorite place to buy tubers or any of your dahlia war stories. I wanna know!

And don’t forget to pin this image so you can find this post for planting time!

Kali

I’m Kali. Oregon mama, farmer’s wife and creator of the Potager book and blog. Join me and as we cook and garden through the seasons!