Cannabis seedlings require the right amount of water, light, and nutrients. Learn how to handle them to get the strongest marijuana plants. Knowing how to care for your cannabis plants at each of the four distinctive stages of their life cycle will provide a healthy, productive garden. Marijuana Seedlings Now that your marijuana seeds have sprouted, what’s next? How do you care for your little baby marijuana seedlings? Your germinated seeds must be placed in a more suitable
Cannabis seedling stage
Keeping your marijuana happy and healthy comes down to how carefully you care for them through each stage of a marijuana plant’s life. Factors such as how much light should seedlings get should be carefully considered as these are especially important in the younger stages of your plant’s life when they are at their most fragile condition.
A marijuana seed that sprouts will split along the seam that joins the halves of its husk. Driven by gravity , the tail grows longer rapidly, screwing its way down into the soil until the root can supply sufficient leverage to raise the husk containing the two seed halves upright.
From that position, the two halves fold out to act as biological solar panels that gather energy and begin a marijuana plant’s first chlorophyll production even as the tiny taproot sprouts hairlike feeder roots that stretch outward to strengthen its grip in the soil.
In this article, we take a look at the ways to protect your seedlings through their most delicate stage of life.
Our guide to the seedling stage for marijuana plants:
What are seedlings?
The key thing to do during this stage is simply to pay attention and keep tabs on every development or change that occurs in your marijuana seeds. When they sprout, the seeds’ seams will split and allow a white tendril to poke through within several hours of this split. This tendril will grow very quickly, moving downward until it’s deep enough for it to hold up the rest of the plant (namely the stalk and the seed husk).
The husk, now split into two, emerges from the ground and functions as a sort of makeshift leaf – in other words, it absorbs energy that can be used to produce chlorophyll within the plant. While you see the stalk growing upwards, you can also be sure that more roots are sprouting and growing downwards at the same time.
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The first two leaves, completely unique from any future leaves that will grow, pop out of the middle of the seed’s split. These leaves are called sucker leaves and mark the beginning of more leaf growth.
Two-lobed leaves will then grow from the middle of the sucker leaves. These two-lobed leaves usually resemble chicken feet, since they have three lobes. After the three-lobed leaves come two leaves with five lobes, and then two more with seven. Seven-lobed leaves are the ones everyone recognizes as the marijuana leaves.
Two lobed leaves will then grow from the middle of the sucker leaves. These two-lobed leaves usually resemble chicken feet, since they have three lobes. After the three-lobed leaves come two leaves with five lobes, and then two more with seven. Seven-lobed leaves are the ones everyone recognizes as the marijuana leaves.
If you were able to keep your marijuana plants healthy throughout its entire sprouting stage, they would most likely go through a very productive vegetative stage. Protecting your young plants is about more than just survival: it’s about investment in your future harvest.
Also read the article How to germinate marijuana seeds for more about germinating tips
This article covers the various elements you will need to keep a constant eye on to ensure the well being of your seedlings. These elements are protection, water, nutrients, heat, and sunlight.
How to protect seedlings
You will need to protect your young plants from more than just discovery by the authorities. Even if you live in a location where growing marijuana is legal, you have plenty to worry about with protecting your seedlings.
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You should keep your plants in some sort of protected area, such as a rooftop, and shelter it using some sort of a transparent, plastic dome or bubble. These domes can keep your seedlings from being eaten by insects, rodents, or other pests, and they are easy and cheap to make yourself.
Simply slice a clear plastic bottle in half, then recycle the top half and keep the bottom half. You should cut small slots around the edges of this half so that your young plant will have some airflow. Place the dome over your little plant, completely covering it. This will have the additional bonus of insulating your plant in case an unexpected frost occurs. In my free Grow Bible, you will find more DIY hacks for your grow.
In addition to insulation and protection, your seedlings will need the most important elements on Earth: water and sunlight. You have to constantly keep the soil and the seedling moist around the clock, and you need to make sure they are receiving plenty of sunlight.
If you live further north, you could have some more trouble with this since your spring days will be shorter than latitudes further south. One big problem that can happen to outdoor growers is their seedlings not receiving enough sunlight. When this happens, the plant stretches taller and taller in an attempt to reach more sunlight, and then it is too tall to hold itself up any longer.
If you want to keep your grow small I can advise a solution like a Pot for Pot. They offer an all-in-one box with everything your plant will need.
If you have space and resources, you can try sprouting your cannabis seeds inside of a closet to begin with. Using the proper equipment in this environment can give your young plants plenty of sunlight, giving them enough energy to sprout large, healthy leaves right from the beginning.
This type of growing would also ensure that their stems won’t get too long and weak; rather, they will be short and strong. You will be able to avoid the hassle of stabilizing tall, weak stems with sticks. If they don’t do this while the plant has leaned to the ground, it could begin to rot.
That being said, if you start to grow your seedlings indoors, transplanting them later will be necessary, which presents its own difficulties and safety concerns for your young plants. Ultimately, it depends on which option is best for you.
How much water do seedlings need
One common problem that occurs when trying to care for a seedling is giving them too much water. It is actually less of an issue having to do with too much water, but actually has more to do with too little oxygen reaching your plant’s roots. This happens most commonly with seedlings being grown in containers since water can only go so far as the walls of the container.
If your plants are being overwatered, you will most likely see symptoms such as drooping leaves. There are plenty of ways to avoid this, however, as long as you keep reading for a better understanding. Your planting situation is the most important factor that comes into play when considering how you have managed to overwater your plants, and how you can fix or avoid the issue.
Overwatering your seeds
Your pot is too big for your seedling
Since a young plant’s tiny roots absorb much less water than their more mature counterparts. If you water as much as the container can hold, these tender roots will not be capable of taking it all in. This situation occasionally referred to as “overpotting,” leads to overwatering. So how do you prevent this situation from happening?
The best thing to do is to begin your seedling’s life in a smaller container to begin with. Once they have grown a fair amount, you can move them to a bigger container. If it’s too late and you need to fix the issue, simply direct your watering to a specific area: a little circle right around your plant. Once the topmost inch of soil is dry again, you can do another round of watering. You can only begin watering normally.
If you plan well enough in advance, you can have a separate container for each of your marijuana plants’ stages of life. If your plants will be living in containers for the entire growing season, you will need to know in advance the size of your last container.
In other words, you will have to have a good idea of how large you would like your plants to become. Because roots grow more rapidly when they are left in one container for a long time, fewer transplants mean a larger size plant (and therefore container). Take that into account when planning your container sizes.
Your pot is too small for your seedling
You can plant seedlings in very small individual containers, such as a solo cup. You can’t keep them cooped up in a solo cup forever, though since their roots will quickly outgrow the small space. If your plants are left in a small container for too long, they will become “root bound.” This means that the roots have wrapped themselves around the outside of the cup, keeping water on the inside from escaping.
Why is being root bound such a bad thing? It can lead to some pretty big problems, including overwatering, nutrient deficiencies, wilting, and more. You can avoid this problem simply by changing the size of their containers as frequently as necessary. (Use these containers)
If your plants’ container does not have an efficient drainage system (i.e. holes punched in the bottom of the container, plus the right kind of soil), overwatering will quickly become a problem that could be life-threatening to your plants.
One way to keep this from happening is to start growing your plants in a soil that drains well from the very beginning. Soils that are clay-based, for instance, retain water and, therefore, should be avoided.
You can also begin with a smaller container, which would help prevent the issue that was mentioned above. Make sure your container has lots of holes where water can drain from.
If you ever notice that water isn’t draining as fast as it should, you can add perlite to your soil to increase the oxygen content. Don’t water your plants quite as often until you notice them drinking more, or try using a Smart Pot instead of a normal pot.
If you follow these tips and are careful about watering your plants, you should be able to avoid overwatering them altogether.
If you’re sure you haven’t been watering your plants too often or too much and they are drooping or wilting, the culprit could actually be a lack of water. Sometimes people who know about the common occurrence of overwatering seedlings have overcompensated, therefore actually watering their plants less than is required.
The roots of your plants need to constantly be able to access water. Plants lose the water they have absorbed through their leaves in a process called transpiration. They do this by sucking up the water from the roots like a straw. If this process keeps going and the roots down below are not receiving enough water, the plant will undergo some serious problems.
If you are able to visibly notice your soil separating away from the container it’s in, you probably have an underwatering problem on your hands.
If your soil is enriched with nutrients and you underwater your plants, the effects will be even more devastating. Your plants will turn a dark green color and will have twisted new growths of a strange color. In this case, the only thing you can do is give your plants more water to re-establish their roots and begin growing once again. If they receive enough water to fight these effects, they will probably be able to combat this situation.
What kind of nutrients
Giving your plants nutrients can come with its own issues. If you give your plants too high a dosage of nutrients, for example, it will turn into nutrient toxicity. Your plant’s leaves will have tip burn and turn darker in color.
Nutrient toxicity can be caused by using a “hot” soil or a type of soil with a lot of nutrients. As long as you are watering your seedlings enough, they should be able to grow out of nutrient toxicity that comes from using hot soil.
Some soils are “slow-release,” such as Miracle-Gro. Avoid these soils at all costs, as they will not help your plant be healthier – in fact, it makes them even more susceptible to nutrient toxicity.
If you provide your seedlings with nutrients when they are too young, they might have a sort of nutrient overdose. As long as your initial potting mix is high quality, you shouldn’t need to worry about adding any more until after a minimum of a few weeks.
If you feed your plants with a large amount of nutrients all at once, you could end up with nutrient toxicity in less than a day. If you’re using a nutrient schedule that comes with the store-bought nutrients, half the amount it says and see how your plants react before adding any more.
From Seed to Harvest: The Life Cycle of Cannabis
Knowing how to care for your cannabis plants at each of the four distinctive stages of their life cycle will provide a solid baseline of knowledge and healthy, productive gardens.
It can take four to eight months to grow a cannabis plant. During this time, it goes through four distinct stages: germination, seedling, vegetative, and flowering. It is essential for cannabis growers to understand each stage in the life cycle so they can properly care for their plants. Each phase requires different nutrients, hours of light, and type of light. There are also different tasks that can help make each stage more successful.
It all begins with a seed. If stored in cool, dark conditions, a cannabis seed can remain viable for years. The best seeds are hard and dry and will be light to dark brown in color. Underdeveloped seeds tend to be soft and either white or green. It’s very unlikely these seeds will germinate.
The seed lies dormant until it is exposed to warmth and moisture. You can germinate your seeds by planting them in a moistened seedling starter mix, covered with plastic and placed on a heat mat. It is important to use a seed-starting mix instead of potting soil.
There is enough nutrition in a seed to feed a sprout for about two to three weeks. Any additional fertilizer can burn your plants at this tender age. Once planted, a seed can take five to 10 days to sprout.
Once your seeds have sprouted, the two seedling leaves will be the first to appear. Place a fluorescent grow light about two inches from the top of your plants for 18 hours per day. You don’t need a powerful light for them in the beginning. When the true leaves appear, your little plants can officially be considered a seedling.
The seedling stage of a cannabis plant can last three to six weeks.
The seedling stage of cannabis plant lasts three to six weeks, depending on environmental factors and the strain you’re growing.
During this time, your seedlings are focusing their energy on growing roots and foliage. Because the roots are so small, be careful not to overfeed or overwater. Use a fertilizer high in nitrogen and be sure to dilute it so you don’t harm your plants.
Fluorescent lights still work well at this point. Set your timer so the lights are on for 18 hours and off for six.
Seedlings are susceptible to pests and disease at this age, so this is a good time to apply a preventative neem oil treatment. It’s much easier to prevent spider mites and powdery mildew than to treat them while your plants are so young. If they do get infested or infected at this age, the stress on your plants will likely produce a smaller harvest down the line.
The vegetative stage of a cannabis plant can last one to four months.
After a few weeks as seedlings, your cannabis plants will outgrow their starter pots and start demanding more food and light. The roots and foliage grow rapidly during this stage, which allows the plant to take in more nutrients and carbon dioxide. Don’t be surprised if your plant shoots up two inches in one day!
If you don’t already know, this is when you’ll be able to identify whether you are growing an indica or sativa. Indicas tend to be short and bushy, while sativas are lanky with less foliage.
You will also be able to identify the sex of your plants. About four weeks into the veg cycle, pre-flowers start to appear. By six weeks in, you should be able to determine whether those new buds are male or female. Most growers remove the males from their garden, so they don’t pollinate the females and cause seeds to form.
When growing indoors, the vegetative stage can last one to four months, or even indefinitely in the case of mother plants. You control the length of this phase by the number of hours of light you give your plants. As long as they receive 18 hours, they will remain in this stage.
During the vegetative stage, you’ll need to trade in your fluorescent lights for a metal halide or powerful LED. This blue light mimics the light in spring and sends the message to grow roots and foliage to prepare for the flowers.
If you haven’t already, transplant your cannabis into larger pots and start feeding them more. As they grow, be mindful you will need to increase the PPM of your nutrient solution and transplant them into larger pots as needed.
At this age, your plants need high levels of nitrogen and modest amounts of phosphorus and potassium. Silicon is also beneficial at this stage because it helps to build strength in the stalk and stems, which you’ll need to support those big buds that will soon grow.
As your plants grow taller and fill out, you’ll need to start pruning and training them. This focuses their energy on growing large colas, opens up the plant so light can reach all the leaves, and prevents fungal diseases by increasing air flow.
The general rule of thumb is to flip the lights to 12/12 and trigger the bloom cycle when your plants are about one third of the size you want them to be at harvest.
The flowering stage lasts six to 10 weeks, depending on the strain you’re growing.
You imitate autumn in your garden when you reduce the light to 12 hours on and 12 hours off, and switch to a red high-pressure sodium bulb. This triggers your cannabis plants to start blooming so they can procreate before they die at the end of the season.
The flowering stage lasts six to 10 weeks, depending on the strain you’re growing. During this time, dense buds covered in a sweet-smelling, sticky resin will form on your plants. This resin is where the THC and terpenes are, and so growers do whatever they can to grow the stickiest colas possible.
Your fertilizing schedule will change during this stage. Start feeding your plants minimal amounts of nitrogen, moderate amounts of potassium, and high amounts of phosphorus. This is the time to add bloom boosters and sugars to your regimen.
Be on the lookout for nutrient deficiencies or toxicities during this phase. Brown leaf tips can signal nutrient burn, while yellowing leaves may indicate a nutrient deficiency. It is normal, however, for the lower leaves to turn yellow towards the end of the flowering cycle, when your plants feed on themselves for more efficient nutrition.
Keep feeding your plants until about 10 days before harvest, and then stop fertilizing and flush your crop. This clears your plants of excess nutrients and is crucial to making sure your end product is smooth instead of harsh.
As your buds grow large and dense, environmental conditions and poor air flow can cause bud rot. If you don’t catch it in time, you can lose all of your plants. Keep a close eye on your buds as harvest time approaches. Inspect your buds often and harvest immediately if you see signs of rot. If you catch it early, you can cut the rot out of your buds and salvage most of your crop. You’ll know your cannabis is ready to harvest when the pistils, or the hairs, turn the color of rust and the resin changes from clear to a milky white.
If you understand the life cycle of cannabis, you’ll be able to care for your plants the right way in each stage of their life and anticipate problems before they occur. You’ll be a better grower and have top shelf smoke to prove it.
Now that your marijuana seeds have sprouted, what’s next? How do you care for your little baby marijuana seedlings? Your germinated seeds must be placed in a more suitable growing medium if you have started them in paper towels, rock wool or peat pellets.
- Small planters utilize your space better
- Small planters grouped together are the most efficient way to use your grow light source
- A small container keeps the roots together and is easier to feed and water.
Planting your marijuana seedlings
Place garden soil in your container up to about 1” from the top. Pack l ightly . Make a hole with a pencil, eraser-side down about ½” deep and put in your germinated seeds, root side down and cover with soil. If your seedlings are already in a seed-starter of some sort, simply bury them in the dirt and cover with ¼ to ½” of soil. Water until the soil is damp, not soaking. It is not necessary, but some marijuana growers like to give the young plants some support. Long wooden kitchen matches (minus the head) work well.
Watering and feeding your seedlings
During this phase, feeding or the adding of nutrients or fertilizer will not be necessary unless you have chosen a soilless mix. Watering should be done perhaps twice per day with a misting bottle for the first few days. How often you water will depend greatly on temperature and humidity. Once the marijuana root is better established, you can slowly cut back to watering every 2-3 days. If you are not sure, you can test by placing your finger into the soil. If it feels dry, then add water. It is important to note that the number one cause of early crop failure is overwatering. Wilting or drooping leaves on your plants are a sign that your plant is thirsty. Plants will revive quickly from such dehydration. While many gardeners use tap or well water, the more sophisticated growers use reverse osmosis, filtered or bottled water and adjust the pH (acidity/alkalinity) of the water. If you are using municipal tap water, fill a bucket or a reserve reservoir and let it sit for several days. This allows most of the chlorine present in the water to evaporate. DO NOT water directly on the plant. They are very delicate at this stage and the stem and roots are easily damaged. Water around the seedlings a few inches base of the plant. It is best to water your plants first thing in the morning for best uptake.
Marijuana seedlings lights
Marijuana seedlings require very little light and can be grown under CFLs (spiral compact fluorescents), tube fluorescents, LEDs and the blue light from Metal Halides (MH). Stay away from incandescent lights as they put off too much heat and too little light. The higher the Wattage your light source, the further away it should be from your seedlings unless you are using LED grow lights with good ones running nearly cold. Too far away and the plants will stretch towards the light making them weak and spindly. Too close and the bright light and heat may damage them, except with LEDs. Let us say you are using fluorescents or LED grow lights. It would be fine to place the light a foot above your plants to start and give the seedlings a chance to ‘harden up’. If they react favorably, you may lower the light a little bit each day until the lights are maybe 4” above your plants. Blue light dominant LEDs and full spectrum LED grow lights offer an excellent start, lower electricity costs and very little if any heat. High Pressure Sodium (HPS) lights are generally not used for seedlings as they do not require the amount of light that HPS puts out, and more importantly, HPS is deficient in blue light. Blue light is what plants use to point them towards the light source. This is called phototropism. Have fun and good luck growing out your marijuana seedlings!