Categories
BLOG

best light for cannabis seedlings

Best Cannabis Grow Light for Beginners

Growing cannabis can be tricky as a beginner, as there are a lot of factors you have to keep in mind. One of the most important, though, is light. Specifically, you need to make sure you’re picking the ideal light for your strain and grow space, and that you’re keeping those lights on a precise schedule. Here’s everything you need to know.

Contents:

With seeds ready to be germinated, pots ready to be filled, and your grow room ready for a long, rewarding season, you may be feeling ready to cultivate some cannabis. You’re just missing one more vital component: the lights!

It may seem like you can just use any sort of grow light and achieve sufficient results, but that’s far from the truth. Different lights are calibrated for different plants and grow spaces. Some may not provide enough light, causing wilting and poor development, while others exude too much heat and cause burning. Others still may hit the sweet spot in terms of supporting growth, but bleed cash in terms of energy efficiency.

It can take quite some time to do research on the right types of lights for cannabis, especially when you don’t have much experience growing. Thankfully, we’ve taken care of the legwork for you, and we’re happy to walk you through what makes a perfect grow light for beginners.

Why Is Light Important for Growing Cannabis?

Light is vital to photosynthesis, and thus essential to the growth of almost all plants. But, the specifics of how cannabis plants receive light are especially important.

For instance, photoperiod cannabis (non-autoflowering cannabis) grows best when it receives a particular amount of light hours per day, usually 16 or more, during the vegetative stage of growth. Once plants hit the flowering stage, that light requirement changes to around 12 hours per day. This, of course, is in line with the shift in sunlight hours that occurs in the spring, summer, and fall.

With that external signal, female cannabis plants (that haven’t been pollinated) know to start shifting their energy towards producing resin-loaded buds. If they don’t receive that signal, however, they won’t know how to distribute the energy they take in from the sun, and your yields will end up smaller than they otherwise would.

In turn, if you’re growing your weed plants indoors, it’s vital to ensure that your grow lights not only simulate the sun’s energy output, but shine on the same schedule as well.

What’s the Best Type of Grow Light for Beginners?

Considering just how important light is in the growing process, beginners should focus on getting a light that not only helps them achieve high yields, but saves them money as well. After all, starting up an indoor growing operation at home can be expensive, even on a small scale.

So, what lights fulfil that role? Well, there are plenty out there that will deliver fine results, and plenty others that’ll save you money, but the only ones that balance both efficiency and power are lamps fitted with LEDs, or light-emitting diodes.

The Benefits of LEDs for First-Time Cannabis Growers

As we just mentioned, there are many benefits beginners can enjoy if they opt for LEDs. Below, we’ll break them down in full.

LEDs Run Cool Despite High Energy Output

With LEDs, depending on which you select, you can achieve comparable energy output to HID, but without nearly as much heat! Thanks to the efficiency of the system, which we’ll speak more on later, all the energy it takes in is directed through hundreds of little lights. Far less gets wasted.

Less Heat Leads to Decreased Water Usage

Thanks to minimal heat in the growing room, you can also expect the water you give your plants to last longer than it normally would. Since you don’t have to deal with rapid evaporation, your watering schedule will not only decrease, but become more efficient.

If anything, all you have to worry about when growing with LEDs is overwatering.

Decreased Water Usage Leads to Fewer Nutrients in Turn

Since many growers include their plant’s nutrients in their water, decreased water usage will also lead to decreased nutrient usage. That, again, is thanks to the fact that plants are able to use said water and nutrients more efficiently.

LEDs Allow for High Light Intensity

The low heat output of LEDs allows for yet another benefit: the potential to offer your plants higher light intensity. See, rather than intense light, it’s intense heat that is the main culprit behind burning plants. If the plants can enjoy more intense light without worrying about heat, however, they can take in a lot more energy.

LEDs Are More Energy Efficient Overall

Lastly, thanks to the fact that far less energy gets wasted on creating heat, LED lamps are the most energy efficient option (relative to their power) of any type of grow lamp. Along with that, you don’t need to have as powerful of a vent or cooling system to account for heat, which you’d need with HID lamps, so you take up even less energy as a result.

What Size Grow Light Do You Need for Cannabis?

The next thing you might be wondering about, then, is what size light you should get. Now, this will depend on the actual energy output of your LEDs (which can vary), along with the quality of your lamp, but there’s a good general outline you can follow as a starting point.

Specifically, assuming you have a decent-quality lamp, you should ensure you get a light with a coverage area of 50 watts per square foot (538W/m²) of growing space. If you were growing in a space that was 5 feet long and 5 feet wide, you’d need a 1250W LED light. That isn’t an exact measurement, of course, and you’ll still need to verify the specifics of your lamp and grow space. In turn, you should check the manufacturer’s guide, and see how they describe their product’s performance.

How Much Do Grow Lights Cost?

Speaking of one’s lamp of choice, though, how much should you expect a grow lamp to cost? Well, keeping the focus on LEDs, you’ll see a great amount of variation in cost.

You can find certain lamps that are cheaper than the vast majority, coming in at well under €100, but they’ll often be low-quality and prone to early burn-out. There are plenty of high-quality LEDs out there, though, some of which can last up to a decade. However, you can also expect to pay quite a bit, sometimes in the €1–2,000 range, for the best and largest options.

In turn, you also have to consider what running the light will cost you once you instal it. Cheaper lamps won’t take up that much energy, but they also won’t offer especially powerful light, so you’ll end up paying more, in a sense, by missing out on optimal yields.

Higher-quality lights may be more expensive out the door, but you’ll know your plants are getting plenty of light, which they’ll be able to convert into massive amounts of buds. You’ll also not have to worry about the increased energy cost of plugging in multiple weaker/low-quality lights.

However, more powerful lights will naturally need more energy to run, and especially powerful lamps will emit enough light to warrant a cooling and ventilation system. That, of course, will lead to a significantly higher energy bill than otherwise.

Beginner-Friendly Lighting Accessories

With your mind more settled on what sort of lamps you’ll be getting, it’s time to think about what accessories you’ll need to install and help them run efficiently.

Adjustable Rope Hangers

Before you get your growing operation off the ground, you need to get your grow lights off the ground. In that moment of need, you should seek out some adjustable rope hangers to carry your lights to the top (of your grow room).

Adjustable hangers are especially useful, as you can adjust the light intensity your cannabis receives depending on its phase and development. If your plants need some extra shine, you can lower the lights towards them, then bring them back up when things get a bit too warm.

Wi-Fi Timer

Timing is another major responsibility that comes with your grow lights, and sometimes you can’t trust yourself to turn them off and on at the right times. When the rest of the growing process gets too overwhelming, consider getting a Wi-Fi-linked timer to turn your lights on and off at precise intervals.

As we’ll further explain in a bit, this sort of timer is especially useful when you need to adjust the light hours between the vegetative and flowering stages of growth. There’s no need to worry about forgetting the schedule when your timer remembers it for you!

How Much Light Do Indoor Cannabis Plants Need?

There are different requirements depending on whether you’re growing photoperiod feminized strains or autoflowering strains, and we’ll discuss them accordingly.

Feminized Strains

If you’re growing a photoperiod feminized strain, you’ll need to change your light schedule based on the phase of development.

During the vegetative stage, they’ll need anywhere from 16–20 hours of light per day. The short nights tell your plant that it needs to spend its energy on getting tall and spreading its leaves, allowing it to efficiently gather energy later on.

Then, when it’s time for them to begin the flowering stage, you should shift their schedule so they receive just 12 hours of sunlight per day. Noticing the longer night (mimicking the change of seasons), the plant takes the signal to shift energy from developing foliage and branches to sprouting buds.

Autoflowering Strains

If you’re growing an autoflowering strain, however, light schedules are a different (and much simpler) story.

See, their name comes from the fact that they don’t rely on light signals to start flowering (unlike photoperiod varieties). Rather, it happens automatically after a few weeks into the vegetative process! Considering that, many growers will leave their autoflowers under the light for 24 hours a day, never turning their lamps off.

However, others argue this is too much for them, and will instead give 18–22 hours of daily light. They do this because plants can get a fair amount of their growing done when they stop taking in energy. Turning off the lights, of course, stops that taking-in process and signals them to focus on growth. This way, plants have enough light to develop impressive results, without your energy bill spiking from constant use.

Don’t Forget to Adjust Your Grow Light

Before we let you go, we want to emphasise again that photoperiod plants will only thrive if they’re on the right light schedule for the vegetative and flowering stages. To assist in that effort, many LED light manufacturers will include a dial, switch, etc. that allows you to switch between modes for each stage.

Along with making that switch, be careful to ensure that you’re raising your lights up in proportion to the vertical height of your plants. The lamps may not generate much heat, but you still want to avoid the risk of burning them.

Other than that, just focus on having a good time!

There are many factors beginners should account for when growing cannabis, and grow lights are one of the most important. Let's help you pick the perfect light.

Mastering The Cannabis Seedling Stage In Just 3 Steps

The seedling stage can be a looming challenge for novice growers. With these three simple steps, however, even inexperienced growers can manage their cannabis seedlings with confidence.

Three simple steps to mastering the cannabis seedling stage.

  • 1. Pick the right genetics, containers, and medium for your seedlings
  • 2. Use the right germination techniques
  • 3. Mastering the seedling stage
  • 3.a. The basics: Optimising light, temperature, and humidity for cannabis seedlings
  • 3.b. Growing seedlings outdoors
  • 3.c. Understanding the seedling stage
  • 3.d. How to water your seedlings
  • 3.e. How to prevent damping off
  • 3.f. How to prevent nutrient problems
  • 3.g. How to prevent pests and bugs
  • 3.h. How to prevent stretchy seedlings
  • 3.i. Know when and how to transplant your seedlings
  • 4. Get growing!
  • 1. Pick the right genetics, containers, and medium for your seedlings
  • 2. Use the right germination techniques
  • 3. Mastering the seedling stage
  • 3.a. The basics: Optimising light, temperature, and humidity for cannabis seedlings
  • 3.b. Growing seedlings outdoors
  • 3.c. Understanding the seedling stage
  • 3.d. How to water your seedlings
  • 3.e. How to prevent damping off
  • 3.f. How to prevent nutrient problems
  • 3.g. How to prevent pests and bugs
  • 3.h. How to prevent stretchy seedlings
  • 3.i. Know when and how to transplant your seedlings
  • 4. Get growing!

Cannabis seedlings can be tricky to keep alive, especially for rookie growers. With a solid understanding of seedlings and their requirements, though, the all-important seedling stage can be a lot less threatening. Keep reading for three simple steps to growing healthy seedlings.

STEP 1: PICK THE RIGHT GENETICS, CONTAINERS, AND MEDIUM FOR YOUR SEEDLINGS

When sourcing your seeds, be sure to actively search out the right strain for you; your experience and skill as a grower, budget, grow equipment, preferences in taste and effect, and whether you’re growing indoors or outdoors will determine which strain will yield the best results for you.

As for the medium, we always recommend growing in a light, well-aerated, slightly acidic soil with a pH of 6.3–6.5. We recommend using between 20–50% perlite in your medium to aid with soil aeration and nutrient retention. The more nutrients you plan to give your plants, the more perlite you should add to your soil to help with drainage and prevent nutrient lockout.

Remember to water just around the stem of your seedlings, and only once the soil has completely dried out (see the section on over/underwatering below for more info). Also, keep in mind that seedlings (especially autoflowering varieties) are extremely sensitive to nutrients. Never plant them into hot (nutrient-rich) soil and don’t start feeding them until they’ve grown 3–4 sets of true leaves.

When it comes to picking pots, we recommend the following approaches for autoflowering and feminized seedlings.

THE RIGHT POTS FOR AUTOFLOWERING CANNABIS SEEDS

When growing autoflowers, we recommend planting them directly in their final pots. Because of their short life cycle, it’s best to avoid putting autoflowering strains through any kind of unnecessary stress, including transplanting. While the exact pot size you use will vary depending on the strain you’re growing and the size of your grow space, most auto growers use pots between 5–15l.

THE RIGHT POTS FOR FEMINIZED CANNABIS SEEDS

If you’re growing feminized seeds, transplanting isn’t as much of an issue since these plants have time to recover from the stress. Using Easy Start germination pots, you can support robust health right from the beginning. You’ll want to transplant your seedlings just before they start outgrowing their starter pots. We typically recommend transplanting once they’ve grown sets of true leaves that spread out to cover the full circumference of their current container.

From here, most indoor growers move their plants directly into 12l pots, but you can go above or below that to suit your particular strain and grow setup. Keep in mind that you can (and should) up-pot feminized photoperiod plants a few times to max-out development, meaning you don’t need to transplant your seedlings into a giant pot right away.

A NOTE ON CANNABIS POTS

From cheap nursery containers to sophisticated smart pots, growers are spoilt for choice when it comes to picking the right container for their cannabis plants. And while it’s possible to grow great weed in cheap plastic propagation containers, there are a couple of things you’ll want to keep in mind when choosing pots for your weed plants.

• Drainage holes

Make sure your pots drain well to protect your plants against fungal pathogens and root rot. If your pots don’t already contain holes (or some other kind of mesh to allow runoff), you’ll need to puncture them yourself.

• Aeration

One of the functions of a plant’s substrate is to serve as a site for air exchange between the roots and the environment. Smart pots like the RQS Fabric Pothelp your plant’s roots respire by allowing more oxygen to reach them. This translates into faster, more vigorous growth, healthier plants, and a better harvest.

• Pot size

Keeping tiny seedlings in huge pots increases the risk of overwatering, as your plant’s roots won’t be big enough to extract all the water from their substrate. Any water that stays in the substrate will effectively drown the roots and attract pathogens and pests into your garden/grow room.

STEP 2: USE THE RIGHT GERMINATION TECHNIQUES

Cannabis seeds need four things in order to germinate: moisture, warmth, darkness, and time. To ensure you grow healthy seedlings, germinate your seeds using one of the following techniques.

• Paper towel method

Carefully place your cannabis seeds between a few moist pieces of paper towel, and place it all in a plastic container with a lid. Keep the container in a warm, dark place (temperatures between 20–25°C are ideal). Leave a slight crack in the lid to allow for some fresh air exchange.

• Glass of water method

Simply drop your seeds into a glass of water and let them sit in a cupboard for 24–48 hours at 20–25°C. Once you see the first signs of taproots sprouting from your seeds, they’re ready to plant. If your seeds don’t germinate after 48 hours in water, switch to the paper towel method. Don’t keep the seeds submerged for more than 48 hours or they’ll rot.

Your seeds are ready to plant once they’ve cracked open and released a small, white taproot. Plant your germinated seeds one knuckle (roughly 3–5 millimetres) deep with the taproot facing down. That way, your seedlings won’t have to reorient themselves.

• RQS Starter Kits

Alternatively, use the RQS Autoflowering or Feminized Starter Kits to provide your seeds with the perfect conditions from the get-go. This kit contains starter pots filled with perlite and beneficial bacteria, as well as a propagator and lights to breathe life into your seeds. carla

STEP 3: MASTERING THE SEEDLING STAGE

Now that your seedlings are in their soil, the real challenge begins. Cannabis seedlings are extremely fragile; armed with nothing but frail roots and a small set of cotyledons (that first set of small rectangular leaves), minor stressors can take down your seedlings in just a couple of hours. By taking the time to understand your seedlings and their specific needs, however, you’ll automatically know how to optimise their environment and help them grow into strong vegetative plants.

THE BASICS: OPTIMISING LIGHT, TEMPERATURE, AND HUMIDITY FOR CANNABIS SEEDLINGS

Seedlings have very particular needs when it comes to temperature, humidity, and lighting, and missing the mark in any of these areas can prove fatal for such small plants. For best results, we recommend growing seedlings in a propagator where you can easily create the perfect environment for them to flourish in.

• Temperature

Cannabis seedlings like daytime temperatures of 20–25°C and nighttime temperatures that are roughly 4–5°C cooler. High temperatures will stress your seedlings and stunt their growth, which, at such an early stage, can prove fatal. Dry leaves with curled up edges are a telltale sign of heat stress. With time, your seedlings might also develop other symptoms, including pale foliage and red or purple stems. Heat stress can also cause weak, wilting leaves with downward folding tips.

Cold temperatures, on the other hand, can freeze a seedling’s cells and affect its ability to transport and use nutrients, water, and oxygen. This will result in stunted growth and eventually death if not dealt with properly. Wilting foliage, slow growth, and poor plant turgor are some signs that the temperature in your grow room or propagator is too low.

• Humidity

While their roots are young and still developing, cannabis seedlings absorb water via osmosis in their leaves. To optimise this process, it’s super important to keep relative humidity levels at 40–60%.

Humidity levels below 20% will seriously stunt the growth of your seedlings and may cause them to develop symptoms similar to some nutrient deficiencies (yellow or spotted leaves). Humidity levels above 60%, on the other hand, will cause your plants to develop wet spots that can cause foliage to wilt or rot, as well as attract fungi and/or other pathogens and pests. Once your seedlings enter the vegetative phase, you should keep relative humidity at 50%.

• Lights

Seedlings are sensitive to light and will burn under strong HID or LED bulbs. Like adult plants, seedlings will develop burnt, crinkled leaves when suffering from light stress. Alternatively, seedlings that don’t get enough light will grow tall and lanky and topple over.

For best results, we recommend growing your seedlings under an 18/6 light cycle using CFL bulbs with a blue light spectrum for the first 10–14 days. Once they’ve developed healthy true leaves and at least 2–3 nodes, you can move them under stronger HID or LED lights to start vegging.

GROWING SEEDLINGS OUTDOORS

Outdoor growers obviously don’t have the liberty of being able to change the temperature or humidity with the push of a button. If you’re an outdoor grower, you have three options on how to tackle the seedling stage:

  1. Most growers choose to keep their seedlings indoors under CFL lights for the first two weeks to protect them from elements.
  2. Alternatively, you can keep your seedlings outdoors during the day (as long as temperatures sit consistently between 20–25°C) and only move them indoors at night to protect them from the cold, rain, etc.
  3. Finally, you can keep your seedlings outdoors permanently in a propagator, greenhouse, or polytunnel to provide shelter and allow you to drive up humidity and manipulate the temperature.

UNDERSTANDING THE SEEDLING STAGE

Inside that dark, hard shell, cannabis seeds house all the necessary genetic information to sprout and grow into big, luscious plants. When exposed to humidity and warmth, seeds are able to absorb water from their environment. This process is known as imbibition, and it’s the key to life for all plants.

Once water enters a seed, it activates special enzymes that trigger the growth of the taproot (the small white root that pops out of seeds when germinated properly). This root starts to push deeper underground in search of more water while the seed sends a shoot up and out of the soil in search of light.

Cannabis seeds already contain two cotyledons (or embryonic leaves) that unravel and push the seed casing from the shoot. After the cotyledons emerge, cannabis plants will develop their first set of true leaves. These will grow out of the main stem and have just one finger.

During the early stages of their lives, cannabis seedlings get all their energy from stores inside the seed. As their roots develop, they can absorb water via their leaves. Once your plants have developed their first sets of true leaves (that is, leaves with at least 5–7 fingers), they are no longer considered seedlings and are officially vegging.

Remember, rapid growth and vibrant green foliage are telltale signs of healthy seedlings.

HOW TO WATER YOUR SEEDLINGS

There’s no universal schedule on how to water your cannabis seedlings. Instead, you’ll need to pay close attention to your plants and their medium. We recommend sticking your finger roughly 2.5cm (1 inch) into the soil and watering only when the soil is completely dry. Also, remember to water your plants close to the stem where you know their roots are. Finally, remember that your pots need to have drainage holes in the bottom so excess water can drain out.

• Overwatering

Overwatering seedlings is one of the most common (and most fatal) mistakes rookie growers make. Unfortunately, it’s an easy crime to commit; scared to let their seedlings’ soil dry out, inexperienced growers often end up watering their plants too regularly. This essentially drowns a seedling’s tiny root system, starving the plant of oxygen and causing it to droop.

Overwatering can also occur when a plant’s container is too big or too small. When growing a small seedling in a big pot, the excess soil can hold water for days in areas untouched by the plant’s roots. What you’re left with is a big container filled with wet soil that’s not only robbing your plant of oxygen, but also creating a breeding ground for fungi, bacteria, and pests.

Similarly, under-potting can be just as detrimental to your plants. Plants that are root-bound take up water very quickly, encouraging you to water them more regularly than necessary, leading to overwatering.

• Underwatering

While it’s not as common as overwatering, underwatering is definitely an issue for some beginner growers (especially those that have been warned about overwatering their plants).

Cannabis plants constantly lose moisture through their leaves in a process known as transpiration (which plays an essential role in a plant’s ability to transport water from its roots up through its stem). Hence, it’s super important they always have access to water from their soil. When a plant goes too long without water, a lot of its vital functions start to slow down. Any roots that dry out completely die off, stunting the plant’s growth or possibly killing it all together (if its root system is underdeveloped).

Unfortunately, the symptoms of underwatering are mostly the same as those of overwatering (drooping and wilting). However, you’ll be able to tell that your plants are underwatered if their soil is bone dry.

HOW TO PREVENT DAMPING OFF

We’ve all been there; your seedlings look perfectly healthy, then suddenly you find them slumped over the edge of their containers. Within 24 hours (or sometimes less), they’ve shriveled up and died.

This phenomenon, known colloquially as “damping off”, is caused by fungi like Pythium, Botrytis, and Fusarium. While these fungi can lie dormant in soil, they grow and thrive in overly wet conditions. Overwatering and high humidity, for example, are some of the most common causes of damping off.

Unfortunately, by the time your seedlings show the first signs of damping off (a limp and discoloured stem), there’s nothing you can do to save them. We just recommend removing the affected seedlings from your grow room or propagator ASAP to avoid spreading the fungi.

To prevent damping off, make sure to keep close tabs on the temperature and relative humidity in your grow space, and avoid overwatering your plants. Also, make sure both your soil and pots drain well.

Finally, to minimise the chance of a Pythium, Botrytis, or Fusarium infestation even further, be sure to always use new soil or sterilise your soil by baking it in the oven until it reaches a temperature of 85°C.

HOW TO AVOID NUTRIENT PROBLEMS

Healthy cannabis plants look vibrant and green, and any sort of discoloration on a plant’s leaves or stems can be a sign of nutrient stress.

Remember, cannabis seeds are jam-packed with nutrients to help get your seedlings through the first stage of their life. Once these nutrients run out, it’s time for you to step in and give your plants the added nutrients they need to veg and flower properly.

• Feeding seedlings

Cannabis seedlings are super fragile and can easily “burn” in nutrient-rich soil. In general, we don’t recommend feeding during the seedling phase. Instead, keep your seedlings chilling in their Easy Start pots until they’re ready to be transplanted and start vegging.

Most blogs and forums will tell you that your plants are ready to veg after two weeks, but that’s far from true; it usually takes about 3–4 weeks from germination for your seedling to use up all the energy stored in the seed, although some plants develop faster than others. But rather than going by time, we recommend you transplant and start vegging your seedlings once they’ve developed at least three nodes and 4–5 sets of true leaves.

• Transitioning to the vegetative stage

Once you’ve transplanted your seedlings into their new pots, give them 3–7 days to adjust. Remember, transplanting is a stressful process, and your plants will need some time to recover from it. Feed your plants too early after transplanting, and they likely won’t take up all their nutrients from their medium, which can cause problems (like nutrient lockout) further down the line.

Once you’re confident your plants have recovered from being transplanted, start feeding them with a mild nutrient solution. An NPK ratio of 4:2:3, for example, is a good starting point for plants just beginning to veg.

• Nutrient burn

Growers usually run into nutrient burn when they feed their seedlings too early or when they transition into the vegetative phase (either because they transplant their seedlings into hot soil or they start feeding with a fertiliser that’s too strong). The first signs of nutrient burn are dark green leaves with burnt tips. Left untreated, nutrient burn also causes leaves to curl upwards.

Luckily, unlike some of the other seedling issues we’ve mentioned in this post, it is possible to remedy nutrient burn. Simply lay off the nutrients for at least one week and water your plants with plain, pH-balanced water. Once your plant starts to grow more healthy, green foliage, slowly dial the fertiliser back in.

Whenever you start feeding your plants, we recommend giving them half the recommended dose of fertiliser during the first week of feeding. This gives the plants time to adjust to their new diet.

• Going organic

At RQS, we’re big fans of organic cannabis gardening. No amount of chemical nutrients could ever compare to the complex mix of microorganisms that exist in organic soil.

When growing organic, the focus is all about building a vibrant soil from the get-go, rather than growing in a stagnant medium and pumping it full of chemical nutrients once a week. While it’s a lot more hands-on, the taste of organic weed is hard to beat. Just remember that organically grown plants typically don’t provide the same yields as their non-organic siblings.

HOW TO PREVENT PESTS AND BUGS

Pests and plagues can destroy seedlings in less than a day. To prevent this from happening, it’s super important to keep the environment around your seedlings clean and at optimal temperatures and humidity levels. Avoid overwatering, and remember to read up on common cannabis pests so you can spot and treat them early. Some common pests to look out for include:

• Fungus gnats

These small, black, fly-like bugs feed off your plants and lay their larvae in wet topsoil.

• Spider mites

Black or red in colour, spider mites live on the underside of leaves and sometimes spin protective webs around healthy foliage. They love hot, dry conditions.

• Leaf miners

These small, slender, winged insects leave irregular snail-trail-like spots on healthy leaves.

• White powdery mildew

As the name suggests, white powdery mildew is a type of mould that forms as a white, flour-like powder on the leaves of your plants.

• Pythium and Fusarium

These fungi can be hard to spot, but white spots on wet topsoil can be an early sign of their presence.

Cannabis seedlings like warm, humid conditions. Unfortunately, pests and diseases also love these conditions. Keeping things extra clean and growing your seedlings in a propagator can help prevent an infestation.

HOW TO PREVENT STRETCHY SEEDLINGS

Seedlings stretch in order to get closer to their light source. To keep your seedlings from developing unnaturally long, flimsy stalks, grow them under blue spectrum CFLs located roughly 5cm from the top of the plants. Also, avoid keeping your seedlings in the dark for 24 hours after germination (a common piece of advice on grow forums), as the lack of light will force your seedlings to stretch abnormally.

KNOW WHEN AND HOW TO TRANSPLANT YOUR SEEDLINGS

Unfortunately, transplanting seedlings is far from an exact science; rather than following a strict calendar or schedule, it’s all about paying attention to your plant and knowing which cues to look out for.

As we mentioned earlier, a good rule of thumb is to transplant seedlings when their leaves fully cover the circumference of their container. After about one week, try checking on your seedlings’ roots. If you can completely remove a seedling and all its soil, it is ready to transplant.

Remember to be very gentle when handling your seedlings and transplanting them. Any minute damage to their roots can result in a ton of stress that, for such young and fragile plants, can take a while to recover from.

GET GROWING!

Now that you know the theory behind growing healthy cannabis seedlings, it’s time to get your hands dirty. Remember to invest in one of our Starter Kits for the best, most reliable results, and keep reading our blog for more tips on growing spectacular weed at home.

Struggling with your cannabis seedlings? Click here for 3 simple steps to growing healthy seedlings, alongside tips for mastering the cannabis seedling phase.