How much should I water my plants without drainage holes?

22 Jul, 2015 · · DIY · 10 comments

22 Jul, 2015 · By Pistils Nursery· DIY · 10 comments

Some pots have drainage; others do not. It’s a pretty straightforward distinction, and yet that little hole at the bottom of your pot means a world of difference in terms of potting, plant care and maintenance.

We field a lot of questions about how to plant in pots without drainage holes. Some people say not to do it at all, arguing that drainage holes are crucial to plant health. Is it possible to keep your plant in a pot without drainage holes? Our answer is yes, but with caution.

What is the purpose of a drainage hole? All plants need water to survive. And yet, over-watering is the most common (and perhaps quickest) way to kill an indoor plant. Drainage holes allow excess water to seep out of pots after watering, ensuring that water does not pool at the base of a pot, protecting sensitive roots from rot, fungus and bacteria.

Here are a few things to remember about keeping plants in pots without drainage.

Rules for Planting: Pots Without Drainage Holes

A little bit of water goes a long way
We normally recommend fully saturating a plant and allowing excess water to flow out the drainage hole, but when a plant is in a pot without drainage, you want to ensure that you water sparingly and slowly. Every drop of water you add to the pot is going to stay in there. And watering slowly helps the water evenly distribute through the soil without pooling at the bottom.

Use Soil Amendments
Soil additives keep your houseplant's soil from being compacted and repelling water. Not only do these amendments provide aeration, but they help water disperse more evenly through the soil. Common additives include perlite, pumice, vermiculite, orchid bark, and horticultural charcoal.

When soil without amendments dries up, it often repels water and makes houseplant care more difficult. The little bits of porous rock and bark help give water more passageways to hydrate your plant's roots.

Use activated charcoal
Activated charcoal has been heated at high temperatures, which increases its naturally absorptive properties. This means that a shallow layer of activated charcoal at the bottom of your pot is actually able to remove some of that excess water, which makes your plant very happy in the case of over-watering.

Another issue that arises from over-watering is fungal and bacterial disease. Activated charcoal has natural microbial properties, and can help deter those harmful bugs. An added bonus!

Think you over-watered? Tip it over.
Yep – Hold the soil back with your hand, and gently tip your pot to the side (or upside down, if possible) to allow the excess water to spill out. You can replace any lost soil later.

Don’t get rained on
If you don’t have a drainage hole in your pot, you probably shouldn’t use it for an outdoor plant, unless the plant will be sheltered from rain. You need to micromanage the amount of water going into your pot; if it get’s drenched in a downpour, all could be lost.

Use the right size
More soil means more moisture for longer. We never recommend moving a plant up to a larger pot more than 1 or 2 inches in diameter. This is especially true with no drainage holes, since, without root mass filling your pot, all that soil will stay soggy for even longer, leading to inadvertent over-watering. We prefer to pot plants that appreciate being rootbound into these pots without drainage: Hoya, Jungle Cacti, Tradescantia, Epipremnum.

If all else fails, repot
You have to listen to your plant. Depending on your space, and your own over-or-under-watering tendencies, your plant may thrive or be miserable in a pot without drainage. If the plant isn’t doing well, gently remove it from the pot and take a look at the roots. Black or brown, mushy roots are a sign of over-watering. Try clipping off any damaged-looking roots, and re-potting the plant in a pot with drainage holes, keeping it just moist until it shows signs of recovery.

Pro-tip: Make it a cachepot
If you’re feeling a bit intimidated about the extra work associated with potting a plant in a pot without drainage, here’s a trick. Find a plastic pot (with drainage holes) that’s just slightly smaller than your planter. Pot your plant into the plastic pot, and then set this inside the planter – if done correctly, the plastic should be hidden, and it will appear as though your plant is potted directly into the planter! You can then take it out to water, and take advantage of the drainage holes in the plastic pot.

Have any advice to share about potting plants with or without drainage holes? Share with us in the comments. Happy planting!