How to care for plants when you're not at home

My job right now requires that I travel 600km away during the week to work there. During this time I will stay in a hotel and my little appartment will just stay cold and empty.

Good for my wallet, bad for my plant

I have a little fern, that is doing a good job cleaning the air, but its not a cactus and he need water regulary. Once week is just not enough.

So I came up with a small irrigation system:

I knew that water will creep along a thread, like oil in a candle. Basically: if one end is wet, the other end will be wet too. Now if I have one end in a Waterbottle, and one end dug into the earth of the plant, the plant will always have enough to drink.

I used a 0,5 l PET bottle and cut the string from a cotton shopping bag. One end I buried in the black earth of my little plant, the other I let hung deep in the bottle.

I put both next to it and let it stand like this for a few minutes.
And behold: the string got gradually more wet from one end to the other.

After another two I began to notice that the bottle was already 1/3rd empty! The rope actually transported too much water, and tried to balance the levels out.

To prevent that, I put the bottle only half as high as the plant.

When I checked the next morning, the plant was still nice wet, but not swimming and the bottle was still pretty full.

I let it stand like this for the next week, and when I came back on a late Friday, the bottel was a third emoptier and the plant still happy.

So with the half liter bottel, I can now sleep well on my trips, knowing that it is well cared for.