How to Grow the Best Cannabis Outdoors in 2025
Growing cannabis outdoors and having your own private outdoor cannabis garden is one of the most rewarding things a first-time grower can achieve. However, you may not have much experience knowing which is the best strain choice for an outdoor cannabis grow, germinating cannabis seeds, when you should be fertilizing outdoor cannabis, watering outdoor cannabis plants, and when to harvest outdoor cannabis.
This article explains all you need to know about how to grow cannabis outdoors. Covering
picking the right cannabis strain, how to germinate cannabis seeds, the equipment required for an outdoor cannabis garden, growing media to use, the best location when growing cannabis outdoors, fertilizing outdoor cannabis plants, repotting outdoor plants, when to harvest outdoor cannabis and provide our top tips for how to grow the best cannabis outdoors in 2025!
Picking the Right Strain for Growing Outdoor Cannabis
When asking how to grow cannabis outdoors, the first thing on your checklist is selecting the right cannabis strain. The strain refers to the genetics that you will choose, which will be either indica, sativa, or hybrid cannabis plants. Working with the right strain best suited for your climate will give you a huge advantage when it comes to growing outdoor cannabis and producing the ultimate outdoor cannabis garden.
Photoperiods or Autoflowering: When Growing Cannabis Outdoors?
You will have two choices when deciding which outdoor cannabis plants you will want to grow. They will photoperiod, meaning the plants will grow in summer and begin to flower around August.
Autoflowering cannabis plants are not dependent on a shorter light cycle, so they will grow for 4 weeks before flowering is automatically induced. Autoflowering outdoor cannabis plants can be harvested every 4 months, allowing a back-to-back harvest over the summer months.
- Photoperiod plants will vegetate for 3 months and take 2-3 months to flower.
- Autoflowering plants have a short vegetative cycle of only 4 weeks.
- Growing cannabis outdoors using autos allows a perpetual harvest every 120 days.
- Autoflowering cannabis plants will grow to a height of 75-100 cm.
The Germination and Seedling Stage for Outdoor Cannabis Plants
Once you have decided which type of plants you prefer for your outdoor cannabis grow, the next step is to germinate your seeds! There will be three different methods for germinating your cannabis seeds and starting your adventure growing cannabis outdoors that are covered below.
Method 1: Using paper tissue towels and dinner plates
The first way to germinate cannabis seeds is to use two wet paper towels and two dinner plates. Wet the tissue paper until it is moist, and place the seeds on the paper towel and plate with a centimetre space between each one. Cover the seeds with the second wet paper towel to create a blanket for the seeds.
Next, you just need to cover tissue paper with the second plate and create a dark environment for them. Within 2-3 days, the seeds will produce a white tail and begin to open, before they are ready to transplant into the chosen growing medium.
Method 2: Using a cup of water
The second method is to take a glass or plastic cup, fill it with 2 inches of fresh water, and put the seeds inside. The seeds will immediately float on the water; however, after 12-24 hours, they will have fallen to the bottom of the glass or cup. Check the seeds every 24 hours until you see the white tail growing out of the seed before transplanting them to the growing medium.
Method 3: Directly into the growing media and pot
The third method is to plant the seed directly into the growing media. You should make a 1 centimetre deep hole for the seed to sit inside before covering the hole with the growing media. Always insert the seed downwards with the pointy side, lightly water it, and then leave it in a warm location. It will take 3-5 days before the seed begins to sprout, and your outdoor cannabis plant is officially on its way to growing!
Tools and Equipment for an Outdoor Cannabis Garden
- Cannabis seeds
- Growing Media
- Plastic or felt pot
- Liquid nutrients
- A sunny location
- Watering can
- Canes for plant support
Best Growing Media to Use for Your Outdoor Cannabis Garden
Now that your seeds have germinated, the next step is to decide which growing medium you will use for your outdoor cannabis plants. You will fill the pots with the growing medium, where the cannabis plant’s roots will grow to access nutrients and water.
You can grow your outdoor cannabis with soil, compost, or coco coir. You can also mix all three to create a custom organic mix with top-quality aeration, drainage, and plenty of nutrients for plants to grow.
Best Pot Size to Use for an Outdoor Cannabis Garden
The general rule when it comes to how to grow cannabis outdoors is that the bigger your pots are, the bigger your outdoor cannabis plants will become. You can choose to use a plastic pot or a fabric felt pot, and it is best to use a size between 30 and 50 liters.
Doing so will allow your outdoor weed plants to become large and develop a substantial and strong root base capable of yielding many buds. If you start your seedlings in small pots, repot them into a larger final container.
Step-by-Step Guide for Transplanting Outdoor Cannabis
Step 1: Fill the larger pot with your chosen growing medium to the top.
Step 2: Dig out a space in the middle of the medium to fit the smaller pot size.
Step 3: Take the small pot, turn the plant upside down and remove the pot.
Step 4: Carefully insert the small plant into the space in the large container.
Step 5: Cover the top with the growing medium once the small plant is inside.
Step 6: Water the top of the soil and allow the roots and plant to settle.
Top tip: When transplanting, always be as careful and delicate as possible. This method can pose a danger to seedlings if careless work is carried out
The Best Location to Keep the Plants When Growing Cannabis Outdoors
When growing cannabis outdoors, the more sun your plants receive, the better. Meaning finding a south-facing location to ensure your plants get the sun from morning until evening, promoting maximum photosynthesis and growing as quickly as possible.
Watering and Fertilizing Outdoor Cannabis Plants
Growing a successful cannabis garden full of thriving plants requires correctly watering and fertilizing them with nutrients. Using a watering can will allow you to consistently provide the same volume of water without the concern that your outdoor cannabis plants do not become underwatered or overwatered. Automated irrigation systems are efficient for growing outdoor cannabis and help save time and labour.
- Using a freshwater source is always best for outdoor-grown cannabis plants.
- Dry soil will result in an under watered plant, affecting plant growth.
- Underwatered outdoor plants will cause nutrient deficiencies, affecting health.
- An overwatered outdoor plant will cause leaves to wilt and the medium to become soggy.
- If using liquid nutrients, follow the guidelines on the nutrient bottles for the best results.
- Water your outdoor cannabis plants at sunrise and again when the sun is setting.
Growing Cannabis Outdoors Inside A Greenhouse
A popular method of growing outdoor cannabis is to use a greenhouse or polytunnel. These are made from glass or plastic and protect your plants from wet weather, cold wind, insects, and animals. A greenhouse is a reliable and safe way to grow an outdoor crop, and is also beneficial for keeping tools and equipment nearby.
When to Harvest Your Outdoor Cannabis Garden
Suppose you are wondering when to harvest outdoor cannabis. In that case, then below is a step-by-step guideline to break down the different stages of a cannabis plant’s life cycle and when to harvest your outdoor cannabis garden. This example is based on growing a photoperiod cannabis plant when the seeds were germinated in the middle of April using a strain with an 8-week flowering time.
April – Week 1 – seedling stage
April – Week 2 – seedling stage
May – Week 3 – the vegetative stage
May – Week 4 – the vegetative stage
May – Week 5 – the vegetative stage
May – Week 6 – the vegetative stage
June – Week 7 – the vegetative stage
June – Week 8 – the vegetative stage
June – Week 9 – the vegetative stage
June – Week 10 – the vegetative stage
July -Week 11 – the vegetative stage
July – Week 12 – the vegetative stage
July – Week 13 – the vegetative stage
July – Plants transition to flower
Aug – Plants will begin to flower
Aug – Week 1 – the flowering stage
Aug – Week 2 – the flowering stage
Aug – Week 3 – the flowering stage
Sep – Week 4 – the flowering stage
Sep – Week 5 – the flowering stage
Sep – Week 6 – the flowering stage
Sep – Week 7 – the flowering stage
Oct – Week 8 – the flowering stage
Oct – Week 9 – HARVEST TIME
Tom Hemp’s 5 Top Tips for Growing Cannabis Outdoors
Tip 1: Using canes to support your outdoor cannabis plants as they grow is an excellent way to produce strong and robust plants. Our tip is to be careful of the roots when inserting the canes, and placing them deep down the side of the pots is the best way to prevent plant stress and keep the roots happy and healthy.
Tip 2: Applying a top dressing of worm castings and compost to the top of your pots every two weeks will ensure a successful cannabis garden. Our tip here is to apply a 1-inch layer bi-weekly and water with nutrients to keep nutrient uptake and availability at the highest level.
Tip 3: When your outdoor cannabis plants are flowering and producing buds, check them daily for caterpillars. The easiest way to combat a caterpillar problem is to use a bacterium named Bacillus thuringiensis (Bt). This organic pesticide will poison the caterpillars and save your outdoor cannabis grow without the need for chemical treatments.
Tip 4: A great way to grow outdoor cannabis and allow you to harvest 3-4 times over the year is to try growing autoflowering and photoperiod plants together. Our tip is to have an area dedicated to auto that can be harvested every 120 days, whilst letting your photoperiod outdoor cannabis plants flower during August and October.
Tip 5: When making a custom organic mix, make sure that the growing medium feels light, spongy, and airy when squeezing with your hand. Cannabis plants require plenty of oxygen around the roots, which will also improve drainage and aeration.
Final Thoughts on How to Grow the Best Cannabis Outdoors
Growing cannabis outdoors is a process and learning curve that takes almost half a year. Making sure that you have the right cannabis genetics that are well-suited to your climate, selecting the best growing medium, and nutrients plays a massive role in the outcome.
Check your plants daily for insect damage and symptoms of underwatering and overwatering. Do your best to support your plants with bamboo canes to make them grow big and bushy, and most importantly, be patient. Good luck learning how to grow cannabis outdoors!
