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How And When To Harvest Dahlia Seeds

How And When To Harvest Dahlia Seeds

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Dahlias are wonderful summer flowers that come in many shapes, sizes, and colors. 

We typically grow them from tubers, but did you know that you can grow these colorful plants from seeds, too?

And now’s the best time to collect them!

Below, you can find more tips and tricks for harvesting dahlia seeds, when the right time comes, storing them, and more info about them in general.

Let’s get started!

When To Harvest Dahlia Seeds

There are many secrets to getting captivating dahlia flowers and one thing all gardeners can agree on is that they will bloom abundantly given the right conditions.

This is excellent because you’ll have a gorgeous garden and some seeds to look forward to. 

Therefore, if you want to harvest dahlia seeds, don’t deadhead every spent flower. Leave some of them to form seed pods and seeds you can later use to grow new plants.

You will have to wait until the end of their growing season – September and October – to harvest dahlia seeds.

And the key for getting viable seeds that will grow into new plants is pollination. Once the flowers begin to fade and wane, you can remove some petals so that bees can access the reproductive parts more easily.

The flower heads will quickly close after the pollination and start producing seed pods.This entire process usually takes about a month to six weeks.

After the pollination, you’ll notice green seed pods taking form. However, they are only ready to be collected once they turn brown.

But this entire process doesn’t mean you can’t deadhead your dahlias and get as many blossoms as possible. Leave a couple of spent flowers about a month before the first fall frost and harvest the seeds some time after it.

This will ensure the seeds are fully developed, viable, and ready for planting.

How To Collect Them

Collecting dahlia seeds is easy and you only require a paper bag and some clean pruners or gardening scissors. This is a time-tested method that will prevent any unwanted seeding or seeds going to waste.

Step 1. Tie the bag around the brown seed pods and snip them to prevent any seed loss if the pods are loose. Or you can simply cut the seed pods and put them in the paper bag.

Step 2. Dry the seed pods for about 2-3 weeks in a cool and dark place (a cupboard, for instance) in the same paper bag. You can also spread them on a baking sheet and leave them in the air to dry out.

Step 3. Then gently open the pods to collect the seeds hiding inside. Each pod will contain about 20 dahlia seeds, which are brown or black, tiny, and flat.

Step 4. Spread the collected seeds on the sheet in a single row and allow them to dry for 24 hours before storing them.

Note: Place another tray or a container nearby in which you can place the collected seeds and separate them from the remaining plant material.

Storing Dahlia Seeds

Now that your seeds are collected and dried, you can store them for the next growing season. Don’t forget to dry the seeds properly or else they won’t last long and eventually turn moldy.

Place the seeds in a paper envelope or some other airtight container, such as a glass jar. Make sure to put the envelope in a dry, dark, and cool spot. A pantry or cool cupboard works best.

Now all that’s left is to label the seeds and wait until the warmth of spring to plant them. Wait until all risk of frost has passed to plant dahlia seeds in a sunny location.

More Dahlia Seed Info

Since it isn’t that common to grow dahlias from seeds, here is more information about this process that can help you decide whether it is the right choice for you.

Do They Turn Into Tubers?

Yes, dahlias will turn into tubers, but you have to be patient. It will take them the entire first year of planting to produce a small set of tubers.

And since these plants are tender perennials and hardy down to zone 7, you will have to dig them up and store them inside overwinter.

Afterwards, you can put them back in the ground come spring or summer and you’ll quickly notice your dahlias sprouting.

The tubers will grow in size year after year and the best part is that flowers won’t change from year to year; they’ll be exactly the same as the first year’s blossoms.

Is It Difficult To Grow Dahlias From Seed?

No, dahlias aren’t difficult to grow from seed. You can even buy dahlia seed packets or simply harvest your own and save some money.

You can sow the seeds in a seed-starting mix and place the nursery tray or pot on a heat mat to speed up the germination process.

Then, you can transplant your young dahlia plants out in the garden once all danger of the last spring frost has passed.

Note: Just remember to harden off the seedlings first to handle the transplant shock a bit better.

Now you know all there is to know about harvesting and storing dahlia seeds for the next year’s planting. This technique will save you a lot of money since you won’t have to buy expensive dahlia tubers. And you’ll get unique flowers to look forward to!