Can you Grow Cannabis Without Grow Lights

Liz Filmer
31 Oct 2023

Can you stick a cannabis plant in a nice sunny window and leave it to grow? Your home offers all the essential benefits, including warmth, natural light, oxygen, protection from the elements, and light.

The more effort you put into a plant, the better your harvest will be. It is surprising how well plants can do without tents, fans, filters and nutrition systems.

Successfully growing a cannabis plant means considering factors such as air, light, temperature, water, and nutrients. If you get those things right, your homegrown cannabis plant could succeed.

Cannabis plants need lots of direct sunlight. To maximise the daily sunlight your plant receives, work with the seasons. The number of daylight hours varies depending on where you live. 

Rooms with southern-facing windows are perfect spots to grow indoor cannabis plants. You should aim for at least six hours of direct sunlight per day. 

There are two types of cannabis plants: auto-flowering varieties and photoperiod varieties.

Photoperiod plants follow a specific light schedule, particularly during the flowering period. They need 12 hours of complete darkness to induce flowering. If you can't get the environment dark enough, the plant will keep growing and may get too big for your space. Our homes are full of light, so to ensure the darkness needed to induce flowering, put the plants in a closet each evening.

Autoflowering plants flower automatically when they reach a particular age; they bloom regardless of how much sunlight/darkness they get. They do not require complete darkness either, meaning you can leave them out overnight, and they will be fine. Auto flowers are also an excellent choice as their growth cycle is shorter. 

Photoperiod plants will take up lots of your time and need your full attention. In contrast, some auto-flowering plants mature entirely in as little as 49 to 56 days.

Choose a strain that will best match the general temperature and humidity of your home. If you have cooler summers, you might prefer an Indica-dominant cultivar that thrives in milder temperatures. If you experience a hot, humid summer, a sativa-dominant strain might be a better choice.

Keep an eye on your plant's growth and development. You should trim any yellowing or dying leaves, keep an eye out for insects and act quickly when you see them.

Rotate your plant as it will grow towards the light. Use a pad and jot down daily details on watering, feeding nutrients, and the growth phase. A record of a plant's entire life cycle will help improve future plants.

More on this topic from Soft Secrets:

Best time to grow weed outdoors

When to harvest outdoor cannabis


Liz Filmer