Table of Contents
- Introduction
- Open the Package Immediately
- Inspecting Your Dahlia Tubers
- Understanding Timing and Your Environment
- Short-Term Storage (1–4 Weeks Until Planting)
- Long-Term Storage (More Than 4 Weeks Until Planting)
- Waking Up Your Tubers (Potting Up)
- Moving Dahlias to the Garden
- Aftercare and Support
- Safety and Quality
- Conclusion
- FAQ
Introduction
There is nothing quite like the arrival of a package filled with dahlia tubers. It marks the unofficial start of the gardening season and brings the promise of spectacular, dinnerplate dahlias and vibrant colors that will last from midsummer through the first frost. Whether you are a seasoned flower farmer or a first-time gardener, receiving that box is an exciting moment that sets the stage for a beautiful summer landscape.
At Longfield Gardens, we take great care to ensure your dahlias arrive in prime condition and are ready for a successful growing season. We work with experienced growers to provide high-quality varieties that are true to type and healthy. This guide is designed to help you handle your new arrivals with confidence, from the moment you open the box to the day you tuck them into the warm spring soil.
Properly managing your tubers when they first arrive is the simplest way to ensure they stay healthy and vigorous. We will cover how to inspect your tubers, how to store them if it is too early to plant, and how to give them a head start indoors. For a broader look at dahlia types and garden uses, see our All About Dahlias guide.
Open the Package Immediately
The first and most important step is to open your delivery as soon as it arrives. While dahlia tubers are hardy enough to travel through the mail, they are living plant materials that need to breathe. During transit, temperatures can fluctuate, which occasionally leads to a small amount of condensation inside the packaging. Opening the box immediately allows fresh air to circulate and prevents moisture from sitting against the tubers.
When you open the box, you will likely find the tubers nestled in wood shavings, vermiculite, or perforated plastic bags. These materials are used to maintain a stable environment during shipping. You do not need to remove the tubers from their packing material yet, but you should open the tops of any bags to allow humidity to regulate. For delivery details, see our Shipping Information page.
Giving your tubers a quick "hello" also allows you to move them out of the path of any household traffic or extreme indoor temperatures. Avoid leaving the box in a very hot hallway or an unheated porch where temperatures might drop below freezing overnight. Keeping them at a stable room temperature for the first hour or two while you perform your inspection is a great way to start.
Inspecting Your Dahlia Tubers
Once the box is open, it is time to take a closer look at your new plants. We want every gardener to feel successful, and a quick inspection is the best way to ensure everything is in order. Healthy tubers come in many shapes and sizes, often depending on the specific variety you have chosen.
For example, a variety like Rip City may produce long, slender tubers.
Meanwhile, Cornel might arrive as plump, rounder specimens.
Similarly, Diva might arrive as plump, rounder specimens, too.
What to Look For
When inspecting your tubers, focus on three main things: firmness, the neck, and the eyes. A healthy tuber should feel relatively firm to the touch, similar to a fresh potato or a carrot. It is normal for them to have a little bit of "give," but they should not feel soft or mushy.
Check the neck of the tuber, which is the thin part that connects the main body to the crown (the top where the sprouts emerge). The neck should be intact and firm. If a tuber is accidentally broken off from the crown, it may not be able to sprout, but most clumps arrive with several tubers attached to ensure success.
Identifying the "Eyes"
The "eye" of a dahlia tuber is the small bump or growth point from which the new stem will emerge. It is located on the crown of the tuber. Do not worry if you do not see green sprouts immediately. Some tubers are "eyed up" when they arrive, showing clear signs of growth, while others are still in a deeper state of dormancy.
If you do not see an eye right away, simply be patient. Depending on the variety and the temperature, it can take anywhere from three to eight weeks for a tuber to wake up and show an eye. As long as the tuber is firm and the crown is healthy, it has the energy it needs to grow.
Key Takeaway: Tuber size varies by variety, so focus on firmness rather than size. A small, firm tuber with a healthy eye is just as capable of producing a massive, beautiful plant as a large one.
Understanding Timing and Your Environment
Before you decide where to put your tubers, you need to know when they can actually go into the ground. Dahlias are tropical plants at heart and are very sensitive to cold. They cannot survive a frost, and they do not like to sit in cold, wet soil.
We recommend waiting to plant your dahlias outdoors until two conditions are met:
- The danger of frost has completely passed for your area.
- The soil temperature has warmed to at least 60°F.
If you are unsure of your frost dates, a quick search for your local ZIP code or a visit to our Hardiness Zone Map can provide the average last frost date for your region. However, remember that the soil takes longer to warm up than the air. If you have a few warm days in early spring but the nights are still chilly, it is best to wait. Planting too early into cold, saturated soil is a common reason for slow starts.
Short-Term Storage (1–4 Weeks Until Planting)
If your tubers arrive and you expect to be able to plant them within the next month, short-term storage is very simple. You want to keep them in a place that is cool, dark, and dry. A basement, a cool closet, or a temperature-controlled garage are all excellent options.
Keep the tubers in the packing material they arrived in, such as wood shavings. This helps maintain a consistent moisture level so they do not dry out too quickly. Make sure the bags or boxes are open so the tubers can breathe. Check on them once a week to ensure they are still firm.
If you notice a tuber starting to look slightly shrivelled, like a raisin, it may be losing too much moisture. You can lightly mist the packing material with a tiny amount of water to increase the humidity, but be careful not to make it wet. Alternatively, you can pot the tuber up in some lightly dampened potting soil to help it rehydrate.
Long-Term Storage (More Than 4 Weeks Until Planting)
Sometimes spring shipping schedules mean your tubers arrive while there is still snow on the ground or many weeks of cold weather ahead. In this case, you will need to provide "root cellar" conditions to keep them dormant and healthy.
The ideal environment for long-term storage is:
- Temperature: Between 40°F and 50°F.
- Humidity: Around 70% to 90%.
- Light: Dark or very low light to discourage premature sprouting.
Avoid storing your tubers in a standard kitchen refrigerator, as the air is often too dry, and ripening fruits nearby can release gases that may harm the tubers. An unheated basement that stays above freezing is usually the best spot. If you use a garage, make sure it is insulated so the tubers never experience a hard freeze. If a dahlia tuber freezes, the cells will rupture, and the tuber will turn to mush when it thaws. For a step-by-step refresher, see our How to Lift and Store Dahlia Bulbs video.
Waking Up Your Tubers (Potting Up)
If you are eager to get started or live in a region with a short growing season, you can "pot up" your dahlias indoors about 4 to 6 weeks before your last frost date. This gives the plants a head start, meaning you will see flowers much earlier in the summer.
To pot up your tubers:
- Fill a container (with drainage holes) about halfway with high-quality, lightly moistened potting soil.
- Lay the tuber horizontally or at a slight angle with the eye pointing upward.
- Cover the tuber with another 2–3 inches of soil.
- Place the pot in a warm, sunny window or under grow lights.
The most important rule when potting up is to go easy on the water. Until you see green growth poking through the soil, the tuber does not have roots to drink up moisture. Too much water at this stage can lead to problems. Once you see a sturdy green shoot, you can begin watering more regularly as the plant develops its root system. For more planting tips, see our How to Grow Dahlia Flowers guide.
What to Do Next:
- Choose a pot that is at least 1–2 gallons in size for temporary indoor growth.
- Ensure the potting soil is "fluffy" and well-draining.
- Wait for the first set of leaves to appear before moving the plant to a brighter spot.
- Maintain a consistent indoor temperature of around 65–70°F to encourage growth.
Moving Dahlias to the Garden
When the weather finally stays warm and the soil is cozy, it is time to move your dahlias to their permanent summer home. Whether you are planting a tuber directly or transplanting a potted dahlia, the site selection is key to a beautiful garden.
Right Plant, Right Place
Dahlias love the sun. For the best blooms and strongest stems, choose a location that receives at least 6 to 8 hours of direct sunlight every day. They also require soil that drains well. If water tends to puddle in your chosen spot after a rain, consider planting in a raised bed or adding organic matter like compost to improve the drainage.
Planting Depth and Spacing
If you are planting tubers directly into the garden:
- Dig a hole about 4 to 6 inches deep.
- Lay the tuber horizontally with the eye facing up.
- Space tubers about 18 to 24 inches apart, depending on the variety. Larger dinnerplate dahlias need more room to breathe, while smaller border dahlias can be planted a bit closer together.
If you are transplanting a dahlia you started in a pot:
- Dig a hole slightly larger than the root ball.
- Place the plant in the hole so the top of the root ball is level with or slightly below the garden soil line.
- If the plant is already tall, you may want to bury the stem slightly deeper to provide extra stability. For a closer look at spacing, see our How Close Can You Plant Dahlia Tubers? guide.
The First Watering
This is one of the most important steps in dahlia care. If you are planting a dormant tuber directly into the ground, do not water it until you see the first green shoots emerging from the soil. The tuber contains all the moisture it needs to get started. Adding extra water to cold soil before the plant has roots can cause the tuber to rot. Once you see green growth, you can begin a regular watering schedule.
If you are transplanting a dahlia that already has leaves and roots, you should water it in well at the time of planting to help settle the soil around the roots.
Aftercare and Support
As your dahlias grow, they will become lush and heavy with flowers. Many varieties, especially the tall decorative and dinnerplate types, benefit from support. It is much easier to provide this support early on rather than trying to prop up a full-grown plant later in the season.
You can use sturdy wooden stakes, tomato cages, or specialized dahlia supports. Simply place the stake in the ground at the time of planting to avoid poking through the tuber later. As the plant grows, use soft garden twine to gently tie the main stem to the stake.
Realistic Expectations for Growth
Gardening is a partnership with nature, and results can vary based on your local microclimate, soil quality, and the weather. Some dahlias will take off quickly, while others may take a few weeks to find their footing. If a variety seems slow to start, give it time. As long as the plant looks green and healthy, it is likely busy building a strong root system underground before it focuses on upward growth.
Safety and Quality
At Longfield Gardens, we want your gardening experience to be enjoyable and safe. Please keep in mind that dahlia tubers and foliage can be toxic to pets if ingested. If you have curious dogs or cats, it is a good idea to plant your dahlias in a fenced area or keep the tubers out of reach during the unpacking and potting process.
We stand behind the quality of our plants with a 100% Quality Guarantee. Our goal is for your items to arrive in prime condition and be true to the variety you ordered. If you notice any issues with the quality of your tubers upon delivery, please contact us promptly so we can make it right. If you experience performance issues during the first growing season, we are here to help with solutions, including potential replacements or credits.
Conclusion
Receiving dahlia tubers is the start of a rewarding journey that ends in a garden filled with spectacular color. By opening your package immediately, inspecting your tubers for firmness, and waiting for warm soil before planting, you are setting yourself up for an easy win. Whether you choose to store them in a cool basement or give them a jumpstart in pots, the key is to work with the plant’s natural needs for warmth and drainage.
Dahlias are incredibly generous plants, often rewarding a small amount of effort with an abundance of blooms that you can enjoy in the garden or in fresh-cut bouquets. We are excited to be part of your gardening journey this season.
Key Takeaway: Success with dahlias comes down to timing and drainage. Wait for warm soil, ensure good airflow during storage, and avoid overwatering dormant tubers.
- Open early: Let your tubers breathe as soon as they arrive.
- Check for firmness: Healthy tubers feel like fresh vegetables.
- Wait for 60°F: Soil temperature is the best guide for outdoor planting.
- Water wisely: Only water dormant tubers once you see green shoots.
For more inspiration and a wide selection of summer-blooming bulbs, we invite you to explore our dahlia collections and other planning guides at Longfield Gardens. Happy gardening!
FAQ
What should I do if my dahlia tubers arrive and it is still snowing?
If your tubers arrive while the ground is frozen, keep them in their original packing material and store them in a cool, dark, and frost-free place like a basement or an insulated garage. Aim for temperatures between 40°F and 50°F to keep them dormant until the spring weather arrives. You can also pot them up indoors about a month before your last frost to give them a head start. For a step-by-step refresher, see our How to Lift and Store Dahlia Bulbs video.
My tubers look small and skinny compared to the pictures. Will they still grow?
Yes, they will still grow beautifully. Tuber size is determined by the genetics of the specific variety; some produce large, chunky tubers while others naturally produce smaller, thinner ones. As long as the tuber is firm and has an "eye" or a healthy crown, it has all the energy required to grow into a full-sized, flowering plant.
Do I need to soak dahlia tubers in water before planting them?
No, you do not need to soak dahlia tubers before planting. Unlike some other bulbs or corms, dahlia tubers contain a significant amount of moisture and energy within their bodies. Soaking them can actually increase the risk of rot. The best approach is to plant them into lightly moist soil and wait for them to sprout naturally.
I don't see any green sprouts on my tubers. Are they dead?
Not at all. It is very common for dahlia tubers to be shipped in a dormant state without any visible green growth. Some varieties are slow to "eye up" and may take several weeks in a warm environment to show signs of life. As long as the tuber feels firm and the neck is not broken, it is healthy and ready to grow once it experiences warmer temperatures.