Watering Indoor Seedlings

Watering outdoors is relatively easy, because you don’t have to worry about over-spray making a mess of something else.

Watering indoors is a bit trickier, because you want to get enough water to your plants without watering the floor or other things in your home.

There are a few ways to water indoor seedlings, depending on whether your seedlings are in pots or in soil blocks.

Watering Seedlings in Pots

  1. Water from the bottom of the pots, by setting the pots / tray in a dish of water for several minutes to a half hour

    1. This is quite effective, but can be time-consuming if you don’t have a standardized setup - and, it can be somewhat messy when you lift the pots out of the water

  2. Water overhead with a small watering can, ideally with a sprinkler nozzle instead of a stream of water

    1. This can work well - but there’s the risk of flattening tiny seedlings with a heavy stream of water

  3. Use a fine sprinkler nozzle on an old dish soap bottle; my favourite is from Lee Valley, pictured below

    1. This method is gentle, works for even really delicate seedlings, delivers enough water to the soil to thoroughly moisten it, and minimizes any mess. Plus, it’s easy to regulate the amount of water that’s squeezed from the bottle.


Watering Seedlings in Soil Blocks

Since soil blocks hold more water, they should be thoroughly watered to keep plants growing well. They can be allowed to partially dry out between waterings (in other words: they don’t need to be soggy all the time)… but when they are watered, they should be watered very well. It’s also important that they NEVER dry out completely.

The easiest way to ensure soil blocks get enough water is to water from the bottom, by soaking the blocks in water.

One way to accomplish this is to set your blocks in a tray that has holes in the bottom.

  • For a home garden scale, one set of mini blocks fits nicely into a plastic quart berry box.

  • For bigger blocks, look for the standard 10” x 20” plant trays with a mesh bottom. Or - check out what you have around - maybe you have some other kind of tray or container with a mesh bottom that would work for the bigger blocks.

The advantage of putting the whole tray into water is that the block will wick up the amount of water it needs, then the tray can be lifted out, allowed to drip for a few seconds, and then set back in place - the blocks aren’t sitting in excess water.

Some people put their blocks on a solid tray, then gently pour water around the blocks to water them. This also works - you just want to be sure to not add too much water, since it’s not ideal for the plants to be sitting in water after the blocks are hydrated.

One other method is to use the bottle tops shown above, to spray the blocks. Two caveats with this method:

  • Be sure to spray gently, so the blocks don’t disintegrate from a heavy stream of water.

  • Make a few passes over the blocks when you water them, to ensure they become thoroughly hydrated. They might need more water than you realize!