cheap wrist watch alarm as outdoor timer?

[hedgeraider]

I want a method to lift plastic covers away from plants automatically after 2-3 weeks from germination: Pint glasses and bottles are great for seedlings, they ensure a 100% start for plants, but the problem is going back to far away wilderness just to take them off and free the plants, after 20 days.

How can i make an automatic system to free the plants?

1/ using a wrist watch, set the alarm to 20 days forwards, and use the alarm's power to feed a capacitor that can melt something or operate an electronic latch? the latch would be attached to a stone in a tree, and when the stone slips downwards, the bottles will be pulled upwards?

3/duracell battery attached to a magnet that lasts around 20 days, and then the magnet unhooks the latch?

/2 using plastic bottles and pint glasses where the top somehow falls away after 20 days. ...



ideas please

 

[hedgeraider]

4/ a very long candle that can go for 2 weeks, and when it gets to the end, i melts a plastic that releases a latch.

 

[stoned-trout]

smoke some more and come up with some new ideas...

 

[hedgeraider]

maybe get a mouse involved. have a cheese that he takes 2 weeks to eat and then it releases a spring.

here's one:

make a strong metal latch out of a dissolveable material that wont survive acid for very long. get the acid concentration just right. the latch will dissolve in controlleable number of days.

 

[hedgeraider]

https://www.youtube.com/watch?v=5Qc_Sy6IAlI

 

[hedgeraider]

https://www.youtube.com/watch?v=PojrpNkGdq4

sulfuric acid dissolving a key

 

[the gnome]

my $$$ on the mouse
mice luvs cheese!!.......it'll work!!