For many years, fluorescent shop lights were the go-to seed starting bulbs for gardeners, but LEDs have quickly replaced them as the standard choice. LEDs are usually more expensive than fluorescent bulbs, but they are very energy-efficient and long-lasting.
Red light stimulates vegetative growth and flowering (but if a plant gets too much, it will become tall and spindly). Blue light regulates plant growth, which makes it ideal for growing foliage plants and short, stocky seedlings (but too much will result in stunted plants).
Most seeds germinate best under dark conditions and might even be inhibited by light (e.g., Phacelia and Allium spp.). However, some species (e.g., Begonia, Primula, Coleus) need light to germinate (Miles and Brown 2007). Don't confuse seed light requirements with what seedlings need. All seedlings require sunlight.
For most home gardeners, a plug-in shop fluorescent or LED light fixture is the perfect type of light to use for seed starting. When shopping for fluorescent lights, look for high-output, full-spectrum (sometimes called “daylight”) bulbs.
A sprouted seed is no longer a seed but a seedling, a miniature plant. The most important thing to consider and deliver is adequate plant light. Seedlings need more light than full grown plants, ideally as much as 16-18 hours a day. Additional light may be required for seeds started during the winter months.
The amount of light each seedling needs will vary from plant to plant. Those that require less light at an adult stage don't need as much as those that enjoy full sun throughout their life cycle. Seedlings exposed to too much light or heat will wither and die.
Seedlings need 14-16 hours of light every single day, without fail. Don't leave them on for 24 hours a day though. Like us, they need to rest at night. So plan to keep your artificial lights on for 14-16 hours during the daytime, and turn them off overnight.
One option is to use fluorescent light. These are available in various sizes, and they generate very little heat. These bulbs are relatively inexpensive, and they do not generate much heat. However, they are not as bright as some other types of grow lights on the market.
While many houseplants can thrive away from any direct light source, seedlings need a good windowsill or some grow lights to provide the energy they need to grow! Moreover, they are sensitive to direct sun, more so than many adult plants are, so picking the right kind of bright spot is crucial.
Generally yes, you can use any LED Light to grow plants, especially white LEDs as they have a good mix of different wavelengths plants need. However, regular LEDs typically don't have sufficient light output or power to help plants flower.
All seeds need water, oxygen, and proper temperature in order to germinate. Some seeds require proper light also. Some germinate better in full light while others require darkness to germinate.
Pre-Soaking.
This method could be the fastest way to germinate seeds. Place seeds in a shallow container in warm water and leave them for 16 to 24 hours (smaller for 16, bigger for 24). Remember not to expose seeds to temperatures higher than 80°F (26.6°C) and not to pre-soak seeds for more than 24 hours.
Seedlings should be watered once a day or every other day, depending on how much sun and heat they get. Remember that seedling roots are fairly close to the surface and they're growing in a small amount of media, so they don't need a deep soak the way larger plants do.
Plants that receive plenty of blue light will have strong, healthy stems and leaves. Red light is responsible for making plants flower and produce fruit. It's also essential to a plant's early life for seed germination, root growth, and bulb development.
Window direction in order of desirability is: south, east, west, north. Even though a south-facing window will provide the best light, keep an eye on seedlings you're growing in this exposure. The sun's rays may be too sensitive for some seedlings at certain times of day.
Standard fluorescent lights are twice as efficient as normal bulbs, while LED grow lights are about five times more efficient than similar regular bulbs. Many regular lights produced much heat and should be hung no closer than 24 inches to avoid burning the plant.
Fluorescent tubes provide one of the best artificial light sources available for plants in the home. They are about 2-1/2 times more efficient in converting electrical energy into light energy than are incandescent sources, making them less expensive to operate.
Most gardeners use either fluorescent lights or light-emitting diode (LED) bulbs. There are other types of grow lights like sodium vapor lights, but they are harder to find and more commonly used in commercial greenhouse settings.
This 100W LED light was just too close to the seedlings, causing them to get burned and turn purple and suffer, they can get burned just like we do in the bright sun! It is true that your seedlings need bright light to grow healthy and strong—but, too bright a LED light could actually damage them if it's too close!
During the seedling phase, when plants are tender, lights are suspended higher. Generally, LED lights should be about 24-26 inches during this phase, and then lowered to 18 to 22 inches during the vegetative and flowering stages of growth.
You need 20-40 watts of power per square foot. Lower wattage LEDs of around 200 watts should sit between 12-20 inches from the top of the plant. Higher wattage LEDs of 1000 watts and above should sit between 36-46 inches from the top of the plant.
Seeds need to be moderately moist to sprout. Seed germination is highly dependent on watering. Too dry and they won't get the message to sprout, too wet and they will rot in the dirt.
Moisture, too little or too much, can be a real killer. Too dry a potting mix results in poor germination and uneven or stunted growth which stresses plants. The combination of too much moisture from overwatering and a warm atmosphere creates ideal conditions for fungal diseases.