A Step-by-Step Guide to Starting Dahlias Indoors for an Early Season Harvest

I bought some more dahlias to plant indoors in pots, but I had no more pots left except for really small 3 inch ones that won’t fit. I usually save a lot from the previous year, but it looks like I didn’t! There are always plastic cups, but they aren’t any bigger than the small plastic pots I still have.

I tried to grow some in flats last year, but it was really hard to separate them. I had to be so rough with the roots that I think I set them back a lot. The newspaper-lined pots have worked so well I am hooked on that method. I then looked for peat pots but those were all small too. There are no garden centers here: I have to look in big box stores. Is there an alternative?.

Dahlias are beloved for their showstopping blooms that inject vibrant color into gardens from midsummer into fall. Getting a head start on the growing season by starting dahlia tubers indoors allows more time for plants to become established before setting them out. This results in faster growth, earlier flowering and higher yields. Follow this simple process for successfully starting dahlias inside

Know When to Begin

Start dahlia tubers indoors 4-6 weeks before the expected last frost date in your region,
For most areas, aim to begin in early to mid April Dahlias need warm soil to sprout and grow properly.

Choose the Right Container

Select a pot at least 4 inches wide and deep or larger to allow adequate room for early root growth.

Pot material can be plastic, terracotta, wood, or other. Ensure there are drainage holes in the bottom.
Darker pots absorb more heat to keep soil warmer than light colors.

Use a Quality Potting Mix

A loose, well-draining potting soil is ideal. Mix in compost for nutrients.

Commercial seed starting or potting mixes work well. Avoid heavy garden soil.
Wet the soil before planting tubers, then let excess moisture drain out. It should be moist but not soggy.

Plant Tubers Correctly

Place 1 tuber in each container, laying it horizontally 2-3 inches deep.

If tuber has a definite top and bottom, plant it right side up. Otherwise, lay it sideways.
Cover tuber with potting mix, leaving just the very top showing.

Provide Warmth and Light

Maintain temperatures of at least 65°F for rapid sprouting and growth.

Place pots in a sunny window or under grow lights on a 14-16 hour daily schedule.
Move plants outdoors during daytime as weather warms above 60°F to harden off.

Water Carefully

Wait to water until sprouts emerge. Damp tubers may rot before sprouting.

When watering, moisten soil without saturating it. Let excess drain out.
Allow the top inch of soil to dry between waterings to prevent tuber rot issues.

Fertilize Lightly

Use half strength liquid fertilizer once sprouts appear and again when true leaves form.

Applying too much fertilizer on young plants can cause leggy, weak growth. Go easy.
Fish emulsion, compost tea, seaweed extract, and all-purpose mixes work well.

Transplant at Proper Time

Move dahlias outdoors when nighttime temperatures stay above 50°F.

Harden off plants first by slowly increasing their exposure to sun and wind.
Plant in garden beds or containers with rich, well-drained soil in full sun.

Starting dahlias indoors extends the growing season for months of vivid color in your garden. Follow these tips to help your tubers sprout successfully indoors and transfer smoothly outdoors. With proper care, you’ll be rewarded with vigorous, floriferous plants and fabulous flowers.

How to Start Dahlias Indoors

FAQ

Do you need to soak dahlia tubers before planting?

Do You Soak Dahlia Tubers Before Planting? Generally, dahlia tubers do not need to soak before planting. However, if they appear dried out and shriveled, you may want to soak them in a bucket of tepid water for one hour before planting.

How long does it take for dahlia tubers to sprout indoors?

A greenhouse, hoop house, or sunny windowsill are great places. It typically takes about two to four weeks for dahlias to begin to sprout up out of the soil. So start this process between five and seven weeks before when you expect to be able to plant them outside.

How do I wake up my dahlia tubers?

The warmth and sun will tell the tuber it’s time to start growing. Do NOT leave tubers outside at night if there is any risk of frost. If you are putting them in a cold frame or unheated greenhouse, make sure you bring them in at night so you don’t lose your tubers to frost.

Should I start dahlias indoors?

This guide unveils the secrets to successfully starting dahlias indoors for an earlier and more rewarding bloom season. Earlier Blooms: Get a head start and enjoy stunning dahlias weeks before those planted directly outside. Pre-sprouting indoors allows them to establish strong root systems before the warmth arrives.

Can you wake up Dahlia tubers?

Let’s dive into the process: 1.**Best Time to Begin**: – The optimal time to start waking up Dahlia tubers is in **early spring**, when the soil temperature consistently ranges between **50°F and 65°F**.Typically,

Can you grow dahlia tubers indoors?

Yes Grow Beautiful Dahlia Tubers Indoors, it’s important to moisten the potting mix before planting the tubers. This will help the tubers retain moisture and start sprouting. Now that you have your tubers and container ready, it’s time to plant them. Follow these steps for successful planting and sprouting of dahlia tubers:

How do you grow dahlias in a greenhouse?

1. Begin by choosing a location with plenty of sunlight and good air circulation. A windowsill or greenhouse is an ideal spot. 2. Prepare your pots or containers by filling them with well-draining soil. Dahlia tubers prefer loose, rich soil. 3. Place the tubers horizontally in the pots, making sure the eyes are facing upwards.