Are cans safe for plants?

[hazelg 10]

I have an abundance of stainless steel beer cans and was wondering if they are safe to use for small plants eg herbs or succulents? many thanks.

[Margarita Ma 10]

I doubt if they are stainless steel as it is too expensive to be used for a throw away item. Anything you use for raising plants needs to have a wide open top for watering and holes in the bottom for drainage. sooner or later, if you do the job of looking after your plants well, they will need to be transplanted to something larger and having a wider top than bottom on your growing container helps to remove the plant more easily than a container with straight sides.

[hazelg 10]

Thanks Margarita Ma! It was more whether the containers will rust etc? I'm more than happy drilling holes in the bottom

[Goldhead 10]

The cans are probably aluminium, and so they won't rust. Aluminium is easily "squidged", unlike the plated steel cans used for food such as baked beans etc.

 

If they prove good, enjoy accumulating more!

[hazelg 10]

Thanks for the advice Goldhead! I work in hospitality so never short of quirky beer cans

[Thorpist 72]

I would hazard a guess that any plant sown in metal would become too cold in winter and too hot in summer due to the high thermal conductivity of metals.

[Aleksandr 10]

I would hazard a guess that any plant sown in metal would become too cold in winter and too hot in summer due to the high thermal conductivity of metals.

I would hazard a guess that this is not true. Good grief.

[Chez2 10]

I would hazard a guess that this is not true. Good grief.

 

It is true for plants outside.

 

A lot of cans are steel with coated insides. Aluminium is more expensive than steel.

 

Pop a plant pot inside the can if you want the can for decoration. Otherwise they are best recycled back into cans.

[Margarita Ma 10]

Also, Aluminium is not generally very good for plants, though there are some that have evolved to take advantage of high levels in the soil. I would not put herbs into soil that was in an aluminium container in case the plant absorbed it and then it was consumed. Succulents that are not going to be consumed might show some interesting effects as plants that are adapted to aluminium tend to have unusual greens.

[Aleksandr 10]

It is true for plants outside.

 

A lot of cans are steel with coated insides. Aluminium is more expensive than steel.

 

Pop a plant pot inside the can if you want the can for decoration. Otherwise they are best recycled back into cans.

It is not true. A highly thermally conductive material such as aluminium will, presumably, allow the soil and hence the plant to heat up and cool down slightly faster than a plastic pot would, but will make no practical difference to the average, maximum or minimum temperatures attained.

[Chez2 10]

It is not true. A highly thermally conductive material such as aluminium will, presumably, allow the soil and hence the plant to heat up and cool down slightly faster than a plastic pot would, but will make no practical difference to the average, maximum or minimum temperatures attained.

 

Ah well, you seem to know better than expert gardeners. In fact, you have just contradicted yourself. Metal containers are not good for plants. The soil (and plant roots) heat up and cool down, hence the issue with using small metal cans. That's why plastic or ceramic pots are better. They don't allow the soil to heat up as quickly.

 

Link to RHS showing pros and cons of different pots.

 

https://www.rhs.org.uk/Advice/Beginners-Guide/Plant-containers