Although most wildflower seeds can simply be scattered on bare dirt, there are several varieties that will have a better germination (sprouting) rate with just a little extra work before planting. Seeds such as Morning Glories, Lupine, Sweet Pea, and more have very hard seed coatings, which you can see just by looking at them. For the most successful (and quickest) germination of these seeds, you can scarify and soak the seeds before planting.
Seed Scarification: nicking, breaking, softening, or otherwise weakening of the seed coating meant to speed up germination.
You can see the hard, almost walnut-like seed coating on these Nasturtium seeds. For best germination, you can nick the outer coating and soak the seeds overnight before planting.
Should I Soak Nasturtium Seeds Before Planting?
Nasturtiums are a beloved flower for gardens large and small With their bright, trumpet-shaped blooms and rounded leaves, they bring color and texture to any garden bed or container As an easy-to-grow annual, nasturtiums can be planted directly from seed into the garden. However, many gardeners wonder if it’s beneficial or even necessary to soak nasturtium seeds before planting. In this article, we’ll dive into the details and explain the pros and cons of soaking nasturtium seeds.
Why Soak Seeds?
Seed soaking is the process of submerging seeds in water before planting them. It’s commonly done to soften the outer seed coating, kickstart the germination process, and improve moisture absorption. Soaked seeds tend to germinate faster, more uniformly, and at a higher success rate. This gives seedlings an advantage, especially in less than ideal growing conditions.
When it comes to nasturtiums, soaking offers benefits but isn’t always required. Nasturtium seeds have a hard outer shell that protects the embryo inside. This shell can inhibit water absorption, leading to slow, sporadic germination. Soaking softens the shell, allowing moisture to penetrate and trigger germination. Soaked seeds sprout faster, taking 1-2 weeks rather than 2-3 weeks typically. They also tend to have higher, more uniform germination rates. During soaking, some seeds that weren’t viable will float to the top, allowing you to remove them before planting. Overall, soaking improves the odds of growing a robust nasturtium bed from seed.
However, nasturtium seeds don’t require soaking. With proper planting technique, regular watering, and a bit of patience, they’ll eventually germinate and grow when sown directly in the garden. So soaking can provide advantages, but isn’t mandatory for success.
How to Soak Nasturtium Seeds
If you decide to soak your nasturtium seeds, follow these simple steps:
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Fill a bowl with room temperature non-chlorinated water.
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Add nasturtium seeds and let soak for 12-24 hours. Gently swirl occasionally.
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Drain soaked seeds and spread out to dry on a paper towel before planting.
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Discard any seeds that floated to the top, as they are unlikely to be viable.
The ideal soaking time is around 12-24 hours. Less than 8 hours may not sufficiently soften the seed coating. More than 24 hours risks over-soaking. Room temperature water prevents shocking tender seeds. And drying prevents mold or rot before planting in moist soil.
When to Soak Nasturtium Seeds
Here are some situations where pre-soaking nasturtium seeds can be beneficial:
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Cold soil conditions – Soaking gives seeds a germination head start before planting in chilly spring ground.
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Dry soil or drought periods – Pre-hydrated seeds are better equipped to sprout and grow in dry soil.
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Indoor starting – Soaking maximizes germination rates for seeds started indoors.
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Old or stored seed – It helps revive older seeds by kickstarting the germination process.
You may choose to skip soaking if planting nasturtiums in warm, moist soil or if using freshly harvested seed. But soaking is a good insurance policy, especially for challenging conditions.
Planting Soaked Nasturtium Seeds
Once soaked and dried, nasturtium seeds can be planted in the garden. Follow these tips:
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Plant 1/2 inch deep in loose, well-drained soil with plenty of sun.
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Space seeds 8-12 inches apart to allow for growth.
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Water regularly to keep soil moist, not soaked, while seeds germinate.
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Thin seedlings to 12 inch spacing once plants reach 2 inches tall.
The soaked seeds should sprout in 1-2 weeks if kept moist. Thinning prevents overcrowding, allowing plants room to reach their full size and flower production.
Risks of Soaking Seeds
While soaking nasturtium seeds can be beneficial, there are a few risks to be aware of:
Over-soaking – Too much time in water can cause seeds to rot and prevent germination.
Premature sprouting – Seeds may begin sprouting before they’re planted in the garden.
Disease – Wet conditions can potentially harbor fungal diseases. Be sure to use clean water.
Freezing damage – Hydrated seeds are more prone to frost or freeze damage if temperatures dip.
To avoid issues, limit soaking time to 12-24 hours, use clean water, plant promptly after soaking, and protect sprouted seeds from cold conditions. With some care, risks can be minimized.
Alternative Germination Methods
If you wish to skip seed soaking, there are a couple alternative methods to potentially improve nasturtium germination:
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Scarification – Lightly scratching the seed coating mimics soaking’s effects.
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Warm water – Soaking in 80-90°F water softens seed coats more quickly.
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Paper towel – Fold seeds between moist paper towels to sprout.
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Direct sowing – Plant untreated seeds directly in the garden as normal.
While soaking is simplest, alternatives like scarification or sprouting seeds on paper towels can also be effective preparation methods.
The Bottom Line
Soaking nasturtium seeds before planting is an optional technique that offers some potential benefits. Soaked seeds may germinate faster, more uniformly, and have higher viability rates. However, with proper care, nasturtiums will grow successfully even when seeds are sown directly in the garden bed without pre-soaking. So it ultimately comes down to your preferences as a gardener. If you want to maximize your odds of robust germination, soaking is certainly worthwhile. But it’s not an absolute requirement. Follow the simple soaking steps above, weigh the benefits against any risks, and make the choice that fits your gardening needs. Either way, with the right care, you’ll be enjoying vibrant nasturtiums in your garden soon enough. Happy growing!
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Common Seed Varieties That Need Scarification
Many native plants and wildflowers require scarification, as they are very likely to have mechanisms in place that control the timing of their germination – a trait that has allowed them to evolve wonderfully in our local climates. When in doubt, assume that your natives need to be soaked before planting at the least!
Note: Most vegetable seeds are soft and do not require any scarification.
Although this isn’t a comprehensive list, here are some of the common garden seed varieties that germinate and grow more quickly with scarification and soaking:
Morning Glories, Nasturtium, and Sweet Peas
Lupine, Milkweed, and Joe Pye Weed
Poppy Mallow, Columbine, and Moonflower
Spinach, Winter Squash, and Beans
Morning Glories are one of the seeds that benefit from scarification and soaking to speed up germination.
How to Speed Up Nasturtium Seed Germination | Scarification Methods
FAQ
How long should I soak nasturtium seeds before planting?
Some gardeners like to soak nasturtium seeds before planting to speed germination. If you do, remember to soak them no longer than eight hours to avoid losing your seed to rot. Nasturtiums like sandy, well-draining soil without too many nutrients, but they do like ample water.
Should you nick nasturtium seeds before planting?
You can see the hard, almost walnut-like seed coating on these Nasturtium seeds. For best germination, you can nick the outer coating and soak the seeds overnight before planting.
Do nasturtium seeds need darkness to germinate?
The distinctive nasturtium seedlings generally come up with 7-10 days of seeding and grow quickly in warm weather. Sow seeds ½” deep (they need darkness to germinate) and 10-12” apart. Soak the seed overnight to enhance germination. They should come up in a week to ten days depending on the soil temperature.
How do you germinate nasturtium seeds?
- Soaking: Soak the seeds in water for 4-8 hours to encourage germination.
- Scarification (Optional): You can also gently nick or file the hard outer shell of the seed to help it absorb water more quickly.
Do Nasturtium seeds need to be soaked?
Several seeds can be soaked to help speed up germination. These can vary, but hard-shelled seeds such as those of the nasturtium greatly benefit from a pre-soak. For seeds that have a softer shell, a shorter pre-soak is required as opposed to those that have a more rigid shell. How Can Soaking be Beneficial? Several seeds benefit from some soaking.
How do you grow Nasturtium seeds?
To soak nasturtium seeds, place them in a bowl of water and let them soak for 24 hours. After soaking, drain the seeds and plant them in moist soil. Nasturtium seeds will typically germinate within 7-10 days. Nasturtium seeds are a delicious and nutritious addition to any garden. They are easy to grow and do not require much care.
How long do Nasturtium seeds take to germinate?
However, soaking the seeds can help to speed up germination. To soak nasturtium seeds, place them in a bowl of water and let them soak for 24 hours. After soaking, drain the seeds and plant them in moist soil. Nasturtium seeds will typically germinate within 7-10 days. Nasturtium seeds are a delicious and nutritious addition to any garden.
How long should Nasturtium seeds stay in water?
Keep the boil in a quiet, safe space, away from crowds and animals. Let the seeds remain soaked in the water for anywhere between 8 to 48 hours. However, it is ideal for keeping the seeds in the water between 12 to 24 hours. When Should You Plant Nasturtiums
Do seeds need to be soaked before planting?
Several seeds benefit from some soaking. By soaking a seed before planting, you can speed up the time required for germination. This process is referred to as imbibition, where the seeds need to take in some water in order to trigger the process of germination.
Can you grow seeds without soaking?
They will still germinate fine without being soaked beforehand, and I have had success growing all of the below plants without pre-soaking the seeds, but germination can be sped up thanks to soaking for up to 24 hours before sowing. There are more examples of seeds that will benefit from being soaked.