Posted on

how to plant weed seeds without soil

Take great care handling seed and seedling. Most flower and vegetable seeds are simply planted directly in the soil, but because of the value of cannabis seeds, germinating seeds prior to planting is encouraged. Growers can achieve a much higher survival rate by germinating in a non-soil medium and then transferring the seed to soil once the tap root has emerged from the seed.

If you love City Paper, get it every day in our newsletter.

Will you support local impact news in D.C.?

Support local news in D.C.!

Once they sprout in one to three days, new seedlings will need lots of light, and fluorescent grow light works best. Give your baby ganja plants 16 hours of light per day.

How to plant weed seeds without soil

In general, a hydroponic grow won’t differ from a standard grow in most ways, aside from considerations needed to keep the tanks full and the room from getting too wet.

LEDs or well-cooled HPS systems are ideal for this, as it can get downright steamy in an enclosed hydroponic set up if the temperature is off. Other than that, the general rules of 18 hours on and 6 hours off apply throughout both seedling and vegetative stages, with the 12 hours on and 12 hours off kicking in once it’s time to flower.

This is kept on a timer and can be adjusted to suit the needs of the plant.

The gist of it is that the roots of the plant grow into an inert soil, such as perlite, and come into contact with a nutrient solution via a couple of different methods.


Once every two weeks, the whole system should be cleaned out to avoid gunking and other nasties that may have built up, which is when you should add more nutrients to the mix.

The main ingredients needed for a healthy plant are nitrogen, phosphorous, and potassium. These come in different blends at different percentages, depending on the stage of growth the nutrients are recommended for.

Unlike the previous two methods, both which are variations of a liquid nutrient bath, this one uses a spray to get nutrients to the roots. Triggered by a timer, the nutrient aerosol is sprayed a few times a day onto the dangling roots of the plant. The roots grow quite long because of this and it allows for a lot of oxygen to penetrate them easily.

pH Levels

Ebb and Flow is probably the most popular beginner method and widely available for sale from a lot of different manufacturers. The way it works is pretty straightforward. A nutrient solution is pumped onto the growing medium the roots are entangled on—Rockwool is very common for this— and slowly drains into the reservoir.

In fertile soil, a lot of the essential minerals for growth are already there for cannabis to use; however, with hydroponics systems, you need to add these yourself. Solutions come pre-prepared to resolve a lot of the guesswork, but knowing what these specific elements are can help understanding in the long run.