Drainage for pot plants

Joly_Roger

I believe some pots don't have drainage holes so you can use them indoors without fear of excess water ruining your windowsill/ table top / carpet, etc... You just need to use good judgment to ascertain how often to water house plants in pots with no drainage holes.

With hole-free pots outdoors it would only take a quick downpour for them to drown your plants. What I do if I require extra drainage, is drill holes in the sides near the bottom, rather then the actual bottom of the planter, so that the bottom can act as a reservoir incase there were a drought.

Also, I never use small pots outdoors, always larger ones which hold so much more water and suffer much less from evaporation due to the surface area to mass ratio being lower. This means they need watering less frequently. The largest pots I never need to water as rainfall is sufficient. The plants much prefer larger pots as they get consistent moisture levels for the above reasons.

Also, larger pots have a greater thermal mass so the roots of tender plants are better protected from frost damage.

SallyForth_2

Joly_Roger wrote: »

I believe some pots don't have drainage holes so you can use them indoors without fear of excess water ruining your windowsill/ table top / carpet, etc... You just need to use good judgment to ascertain how often to water house plants in pots with no drainage holes.

With hole-free pots outdoors it would only take a quick downpour for them to drown your plants. What I do if I require extra drainage, is drill holes in the sides near the bottom, rather then the actual bottom of the planter, so that the bottom can act as a reservoir incase there were a drought.

Also, I never use small pots outdoors, always larger ones which hold so much more water and suffer much less from evaporation due to the surface area to mass ratio being lower. This means they need watering less frequently. The largest pots I never need to water as rainfall is sufficient. The plants much prefer larger pots as they get consistent moisture levels for the above reasons.

Also, larger pots have a greater thermal mass so the roots of tender plants are better protected from frost damage.

Thanks for all of this, very interesting and useful advice.

Jake'sGran

dollparts wrote: »

Why would they sell pots with no holes if they are so critical to the survival of whatever you are growing?

As if I didn't have enough to get my head around, now I have to get drilling as well!

.

I was surprised when I read you earlier message. If you drill a hole/holes in terracotta I think it would crack across i.e. the pot might split in half. Was the pot in question intended for plants?

tim_n

If you're making a self watering pot, you buy two plastic pots the same and put one inside the other. The 'inner' pot you knock the holes through from the moulding (hot nails, drill etc) the outer pot acts as the resevoir.

Put thin strips of cloth through the holes into the resevoir. Excess water drains into the resevoir and is drawn up by the cloth to the roots as it is needed.

balloo_2

20mm Gravel not the fancy coloured stuff plain ordinary Gravel in B&Q £1.82 or ask at a local building site for a bucket full. If you don't ask you don't get innit

dollparts

Jake'sGran wrote: »

.

I was surprised when I read you earlier message. If you drill a hole/holes in terracotta I think it would crack across i.e. the pot might split in half. Was the pot in question intended for plants?

Yea, it is labelled a plant pot, in a garden centre, in the flowerpot aisle so I have a feeling I'm not being wound up!

Sorry to labour the point and please forgive my naivety- but having to drill holes or channel hot nails through plant pots seems the most ridiculous thing I have heard all day! True, there is the cost issue, but it rather seems to me that it would be like making shopping trolleys with only 2 wheels-if we support them upright they will move along the aisles anyway?

Ok, I'm being sarcastic, forgive me. Maybe I am just an overwhelmed beginner who cannot move more than 2 metres in the garden without coming up with another question to ask!

savemoney

The reason of why putting a hot nail in a pot to make a hole is to allow drainage but also there is a small risk of breaking the pot when drilling, going through with a hot nail lessons the risk as it fuses the plastic

onejontwo

Where do you get your pots from? The reason I ask is that as far back as I can remember, all the plastic and terracotta pots I have bought (which included 12 terracotta pots last week) all have had drainage holes.

Kay_Peel

Plant pots have holes and they are used to grow a living plant. Pot holder have no holes and they are usually decorative. You put a plant pot in a plant holder to stop water and soil escaping onto floors and carpets, usually.

Perhaps the OP has a plant holder - in which case I would say - don't ruin it by drilling holes. You'll need it for another purpose. Instead, try and find a simple plastic pot or terracotta pot with drainage holes that will be fit for purpose.

Jake'sGran

tim_n wrote: »

If you're making a self watering pot, you buy two plastic pots the same and put one inside the other. The 'inner' pot you knock the holes through from the moulding (hot nails, drill etc) the outer pot acts as the resevoir.

Put thin strips of cloth through the holes into the resevoir. Excess water drains into the resevoir and is drawn up by the cloth to the roots as it is needed.

I never feel that I am watering my tomatoes correctly. Would this reservoir method work for them?. I imagine it would be better if the pot containing the tomato plant was a bit smaller than the reservoir one?. Is this what you meant? I use the black plastic tubs from the local supermarket and one inside the other would be a tight fit i.e. no space for the reservoir.