Can you help me with 3 of my sick plants?

Question

To start this off, I live in the coast of Lebanon, where the average summer temperature is 30 degrees celsius. Here are pictures: https://imgur.com/a/VAmKNur I have 3 plants that I need help with

1) The mints:I’ve had the plant for about 2 weeks. I noticed the browning of the leaves after about 2 days. There are no insects and it hasn’t been repotted or anything like that. The soil I guess is normal garden soil. I water it at least once a day with tap water (thats not drinkable). I heard that mint thrive in the sun, so I haven’t put it in any shade yet. However the soil content is little, to the point that if I were to water the plant, water would directly flow from under the pot. So, I think I should repot it with more soil. The leaves are browning and getting thin. Brown parts are also spread all over the plant, like some leaves have a small dotted brown part.

2) Clemantis: I don’t really know if it’s really a clemantis, but I’ve asked online and that’s what it appeared to be. I’ve had the plant for about 3 weeks. It got sick a day after planting it in a pot. It has no insects and I recently repotted it hopping that it would become better. I was advised to add normal gardening soil under and light brown soil on top (I feel like this was a mistake though). Same as the mint, I keep it fully exposed to the sun. But when I first got it, I always watered it once a day as I was told. But a week ago I realized the the dirt was always so moist and found out that the pot’s drainage holes weren’t fully open. So I opened the holes and repotted the plant. It’s not getting any better.

3)Oleander: I used an app to identify this plant. Same as my other plants in exposure, sickness, and insects. I was told it likes water, but I then read online that leaves yellow due to excessive watering. So I stopped recently. It’s leaves turned yellow a day after I got it. And now the green leaves seem to be drooping for some reason. It’s potted in a mix of light brown soil and normal gardening soil. This is an old text, recently the green leaves of the oleander got so frail and weak that they were blown away by the win, one of the branches (stems?) doesn’t have any leaves at all. As for the light brown soil I keep talking about, I noticed that it gets dry very quickly I think.

Answer 1

Overwatering will be the cause in all cases. The soil must dry out thoroughly down to at least 2 or 3 inches before watering again. “Water daily” will not be something a gardening professional should say, as different plants and climates require different watering schedules according to how often they dry out down to a certain depth.

“Water once the top of the soil is completely dry down to 2 or 3 inches” will be the better way to water. This will ensure that you have no problems in the future. You will also want to treat with a fungicide.

As always, it is best to care for plants according to each individual plants’ requirements. These articles will help:

https://www.gardeningknowhow.com/garden-how-to/info/using-fungicides-in-garden.htm

https://www.gardeningknowhow.com/edible/herbs/mint/how-to-grow-mint-plants-in-your-garden.htm

https://www.gardeningknowhow.com/ornamental/vines/clematis/growing-clematis.htm

https://www.gardeningknowhow.com/ornamental/shrubs/oleander/oleander-growing-tips.htm