Delphiniums, also known as larkspurs, are popular garden plants that produce tall spikes of beautiful flowers in shades of blue, purple, pink, red, and white. They are loved for their stately elegance and ability to add vertical interest to beds, borders, and cut flower arrangements.
When starting delphiniums from seed, it can be tricky to identify the young seedlings that emerge Unlike many plants, delphinium seedlings look quite different from their mature form. Knowing what to look for will help you successfully grow these flowers from seed
In this article, we’ll cover everything you need to know to recognize delphinium seedlings, including:
- The timeline for emergence and growth
- Distinguishing features of new seedlings
- When true leaves start to develop
- Differences between seedlings and weed imposters
- Tips for caring for young plants
When to Expect Delphinium Seedlings
Delphinium seeds can take 14-21 days to germinate after sowing. The timing depends on soil temperature, soil moisture, planting depth, and seed freshness.
During germination, the seed will swell, burst open, and put out a white taproot. Soon after, the first round embryonic leaves known as cotyledons will emerge from the soil’s surface.
The cotyledons look like rounded paddles and do not resemble the mature foliage. After the cotyledons expand, the first true leaves will begin growing. It takes 4-6 weeks from sowing for the seedlings to reach this stage.
Identifying Features of New Delphinium Seedlings
When delphinium seeds first send up their sprouts, they can be distinguished by:
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Location – Emerging approximately where seeds were sown
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Timeframe – Appearing 2-3 weeks after sowing if conditions are right
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Pair of round cotyledons – These embryonic first leaves look like paddles or spoons. They do not resemble the mature leaf shape.
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Leggy growth – The cotyledons and stem may stretch tall with few leaves in search of light.
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Smooth texture – No fuzz or hairs on the leaves initially. Mature delphinium foliage is downy.
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Pale green color – New growth looks light green and translucent. It will darken as the plant matures.
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Slender stem – The stem is thin and wire-like, not thick like the mature plant.
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Slow initial growth – Seedlings establish roots before gaining size rapidly. Growth speeds up after 4-6 weeks.
Transition to True Leaves
After 4-6 weeks, the seedling’s first true leaves will begin to grow. These look more like the leaves found on a mature delphinium plant.
Signs that a delphinium has its true leaves are:
- Jagged, lobed leaf edges
- Leaves arranged alternately on stem
- Leaves often clasping the stem
- Fuzzy, downy texture on leaves
- Darker green color vs cotyledons
- Faster, more vigorous growth habit
Once the true leaves emerge, the seedling is past the most vulnerable stage and survival rates increase. Now it can focus energy on above ground growth rather than root development.
Differences Between Seedlings and Weeds
Inspect seedlings carefully to ensure they are delphiniums and not weeds. Some weed seedlings may resemble delphinium sprouts. Features that can help correctly identify delphinium seedlings are:
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Emerging near where delphinium seeds were sown
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Round cotyledon shape
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Alternate leaf arrangement (weeds often have opposite leaves)
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Hairy, fuzzy texture on leaves
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Purple-tinged stems
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Rapid vertical growth pattern
Compare suspicious sprouts to the location of sown seeds and reference seedling images to positively identify delphiniums. It’s better to err on the side of caution and remove questionable plants before they overtake desired seedlings.
Caring for Young Delphinium Plants
To maximize growth and survival rates of new delphinium seedlings:
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Provide consistent moisture – Avoid letting the soil completely dry out.
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Give partial sun – Morning sun is ideal, avoid hot afternoon sun.
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Use row covers – Protect from frost and pests with fabric row covers.
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Allow space between plants – Thin seedlings to 4-6 inches apart once true leaves appear.
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Fertilize lightly – Use half strength liquid fertilizer once a month.
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Plant in garden promptly – Transplant to the garden after 12-16 weeks indoors.
With the proper care, those tiny, fragile delphinium seedlings will grow into stately beauties over the season. Getting them off to a good start is key. Understanding their appearance and needs as new sprouts is invaluable for successfully growing delphiniums from seed.
A Visual Guide to Identifying Seedlings
To summarize the key identification features, here is an overview of delphinium seedlings at different growth stages:
Cotyledon Stage
The first leaves to emerge are called cotyledons. They look like small spoons or paddles.
<img src=”http://garden.org/pics/2014-03-21/susanlyn/b4d84c.jpg” width=”150″>
Round cotyledon leaves do not resemble mature foliage
First True Leaves
After 4-6 weeks, the true leaves that look more ferny and downy will grow.
<img src=”https://i.pinimg.com/originals/f3/f4/7f/f3f47ff516756cdb0fa279fdcbfddd6f.jpg” width=”150″>
Early true leaves are often rounded before deeply lobing
Mature Seedling
Given time and care, the seedlings stretch upwards and fill out in size.
<img src=”https://i.etsystatic.com/5689814/r/il/dd6abd/1646889435/il_fullxfull.1646889435_a5io.jpg” width=”200″>
A mature seedling stands 8-10 inches tall with multiple leaves
By recognizing the distinctive traits of delphiniums as they emerge and grow, you can confirm seedling identity, provide proper care, and successfully cultivate these flowers from seed. With the right start, your garden will soon be graced with a vision of delphinium beauty.
Choosing the Right Seeds
The first and most important step is to choose high-quality delphinium seeds. Look for seeds from reputable suppliers to ensure the seeds are fresh and viable. Older seeds may have reduced viability and germination rates. Delphinium seed varieties are diverse. Each type exhibits distinct features, such as flower color, height, and stem strength. Tailoring your choice to your garden’s needs ensures further success. If you’re not the type to cut your delphiniums down and stake them, pick one of the shorter types.
- Katrina and Jason Hindmarsh of New Zealand Delphiniums are great at breeding and growing Delphiniums. Their New Millennium Delphiniums are known for always doing well, having strong stems, bright colors, and being able to handle heat.
- Burpee is known for making high-quality seeds, and I’ve always had great luck with theirs sprouting. There aren’t many types of delphiniums they sell, but they do have some unique ones, like a red one!
- Geoseed is a small company out of South Carolina. They have more kinds of Delphinium seeds than anyone else I’ve seen, and they sell in bulk.
- We’ve had great luck with the seed from True Leaf Market. There are a lot of colors to choose from for both the Pacific Giants and the shorter Magic Fountains. The seeds can be bought in larger quantities, and the prices are great.
When you get your seeds, you should put them in the freezer for at least 48 hours and keep them there until you’re ready to plant. This will help stimulate the natural conditions that these seeds need to germinate.
Essential Tools For Starting Delphiniums
We use a germinating mix that is fine textured and contains natural microbes called Mycorrhizae that help support root growth. We found that once we switched the plant growth had more vitality and strength. When seedlings are healthy, they are less prone to disease.
A heat mat will accelerate seed germination and encourage root development by maintaining soil temperatures at approximately 70º F. It really is a game changer for germinating any plant you want to grow from seed. You may not have a lot of control over the air temps but these mats will give consistent heat where it counts: at the root system.
Don’t forget to label your plants! You’ll never figure it out later. Just some 4” wooden markers will do the trick. We always put the name of the plant and the planting date on the tag.
When the plants are young or still germinating, I would use a mister to keep the soil mix damp. After the plants have some strength you can use any watering tool that has a soft flow nozzle on it. We use the Dramm 1” diameter nozzle. It can saturate the soil without disturbing the plants and soil.
The soil mix has enough starter nutrients for germination. Once the plants have their first or second leaves it’s time to feed the seedlings for good strong growth. We’ve always added liquid fertilizer to our watering regiment. There are two basic options: the first is using an organic fertilizer like FoxFarm Big Bloom® Liquid Plant Food Concentrate or non-organic but very effective Miracle-Gro® Water Soluble Bloom Booster Flower Food. Both work great but Miracle-Gro is more cost effective if you are on a budget.
SOWING DELPHINIUM SEEDS | foolproof seed starting technique | FLOWER FARM VLOG | kitchen roll method
How to plant Delphinium seeds?
Here is the process: choose a tray with drainage holes, and fill it full of moist seed starting mix. sprinkle the delphinium seeds over the potting mix. cover the seeds with 1 cm layer of pumice, similar to perlite. I used vermiculite. Cover this with layers of wet newspaper.
How long do Delphinium seeds take to grow?
Seedlings started to germinate within 17 days, and continue to do so. Delphinium seeds are among the list of flower seeds that are perfect to start indoors in winter. Sow delphinium seeds 6 to 8 weeks before last frost date. Delphinium seeds take three to four months or more to grow to maturity from planting. How Fast Do Delphiniums Grow From Seed?
How do you know if a Delphinium is a good plant?
Vibrant green foliage, sturdy stems, and well-formed buds are positive signs of a robust and flourishing plant. Cultivating delphiniums from seed grants you access to a wider array of varieties and proves cost-effective in the long run.
Can you grow Delphinium seeds without stratification?
Delphinium seeds have improved germination with cold moist stratification. If you plant without stratifying, germination may result in lower numbers of seedlings. A cold moist chill in the fridge will soften the seed coats. You may even have some sprout while in the fridge. Do I Need To Soak Delphinium Seeds?