How to Germinate Seeds Quickly - A-Grade Hydroponics

How to Germinate Seeds Quickly

Growing your favourite plants from seed can be extremely rewarding; there is something special about watching that first seed pop!

But sometimes it feels like your seeds will never germinate; how long is it meant to take anyway?

Every plant is different, and some seeds will take longer to germinate no matter what we do. Under optimum conditions tomato seeds will pop around 4-6 days, while parsnip seeds will pop around day 14. And an avocado seed can take 2 months to germinate!

Knowing what you’re working with will help avoid the “will they or won’t they?” germination jitters; so be sure read up on the seeds you are about to germinate.

If you want to germinate seeds quickly, and well, you will first need to create the optimum environment.

Please note that the guide below is for seeds like tomato, Cannabis, lettuce and wheatgrass. Other types of seeds may require different conditions to germinate.


  • Humidity dome/propagation kitHobby Propgation Pack
  • Grow cubes or coir seed starters
  • Jugs for soaking seeds & grow cubes
  • Measuring jug & pipette
  • Root tonic
  • Heat mat & thermostat controller (if necessary) 




  • Seeds that are old, large and/or have a tough shell will benefit from soaking overnight. An effective scarifying solution is 1ml of hydrogen peroxide mixed with 1L of water.
  • Prepare humidity dome. Make sure it is clean, and preferably sterilised.
  • Remove cubes from solution and give a gentle squeeze so the cubes are not saturated but are still holding a substantial amount of solution.
  • Place seeds “pointy” end facing down and push in, so the husk of the seed is about 1-2mm under the hole surface level.
  • Arrange cubes on base tray. Place dome on tray and close all the vents – 100% humidity is critical until germination.
  • Make sure temperature within the humidity dome is between 20-25°C.
  • If necessary, arrange heat mat and thermostat controller so that the heat mat is under the humidity dome and the thermostat probe is in the humidity dome. Set thermostat controller to 24°C.
  • If the conditions are flawless, the seed will say ‘hello!’ around days 2-5.
  • If the seed has not germinated within 7 days mix up some root tonic solution (75ml per 1L of water) and pour approx. 100-200ml into the tray).

Once your seeds have popped, follow your usual light and feeding procedures. Good luck!

Look out for our next tutorial Why Haven't My Seeds Germinated? 


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