I can see that you don't have a lot of exposed soil, but mulching it may help a little. I think that small amount of soil, touching the walls of a terracotta pot in direct sun, is going to heat up and dry out fast. Blocking the sun from shining directly on the soil/pot will help. In the AZ summer I often place my pots inside of a larger pot or container, perhaps even a cardboard box, so that the sun hits the outer container and doesn't heat the actual pot as much. If your pots are too heavy to lift you could even try leaning cardboard, cloth etc to block the sun.

Another thought is that the floor of your balcony (I assume it's cement) is conducting heat to the pots as well. I have that problem with my brick patio acting like a giant frying pan in the summer, so I set my pots on a few small pieces of wood so they aren't touching it. (If you do that, be sure you aren't blocking drainage holes.)

@iandyaz Thank you very much for your response. The problem is I do not have large trees. I am on the 6th floor. And the shade of the balcony is too high to provide shade early. Today I saw that the sun light hit the pot till 11 AM. I had cut out pieces of styrofoam and kept it beside the pot so it might provide a barrier between the sunlight and the pot , but the soil was hot.

@sunnyvalley Thanks a lot. I have two A4 paper cardboard box in my home. The pots are not on the floor they are on a wooden plank.Can I mulch cactus? I will try your ideas by the will of God and hopefully he will make everything alright. today there were 5 flowers blooming in one cactus -I love this plant and don't want to lose it.

It sounds like you may have two problems going on. Too much sun and too much water. We routinely have temperatures in the low 100s.

Sun/Shade/heat: I keep my echeveria and sempervivum where they are in dappled shade from a nearby thin desert tree until about 11. Then as the sun shifts, they go into in bright shade from an overhang for the rest of the day. You might be able to stretch a light fabric such as cheese cloth in a way to cast a bright shade.

You've probably noticed that glazed pots become far hotter than terracotta pots, so hot they can burn your hands and kill the plant. Favor terracotta if it is available, as it "breathes" - the evaporation of moisture laterally through the clay cools it.

If you can't solve the sun problem, and slipping one pot inside another (as SunnyValley recommends) gets too heavy or too expensive, try re-potting, and line the sides of the pots with thick bubble-wrap. You have to tape the bubble wrap to the top edge of the pot while you are potting, and after you are done you can remove the tape. That has worked for me in places where I can't get a potted plant out of the sun. But the plastic lining means the pot doesn't breath, so you need to be careful about over-watering (see below).

Soil: In the photo, the soil looks much too rich, and it will hold too much water. If you can find bagged potting soil formulated for palms and cacti, that is what you want. It holds just enough moisture, but not too much. If you can't find it for sale, try mixing gritty soil, sand, a very little bit of rich soil. But be wary that builder's sand may have salts in it that need to be washed out thoroughly first.

If you can find washed pebbles, cover the top of the soil with a layer of pebbles 1 to 3 inches deep. This minimize the rate of fluctuation of both temperature and moisture content.

Water: I water my potted cacti and succulents at this rate, based on average daily high temperature:

90+ degrees = once a week

80+ degrees = alternate weeks

70+ = every third week

60 or lower = one watering per month.

Yes, even when temperatures are 106 in the shade, I water cacti and succulents only once a week.

When I water, I give enough that it flows abundantly out the bottom of the pot. This washes away salts and minerals that can build up in the soil.

Try not to get the plant itself wet; succulents don't love this, and the little drops of water act as a lens and can make burned spots. If you have mineral-rich water, droplets will leave behind whitish spots on the leaves.

Lifting the pots on clay feet or pebble or pieces of wood, to allow quick drainage as described above by SunnyValley, is important advice.

I feed cacti and succulents with a half-strength water-soluble balanced fertilizer (5-5-5 or 10-10-10) only once a month, only in the growing season.

Note that cacti sunburn. Potted ones should not be rotated; their skin grows sun-tolerant on the side toward the sun, but does not develop sun tolerance on the side away from the sun. Yellowing of the skin is sunburn. It can be eased by draping cheesecloth over the cactus until autumn.

Good luck with this. You should be able to make a very nice garden even in limited space.

Thank you very much for the details suggestions. I think as you said for the succulents it is too much water, and poor soil and heat. I have transplanted them in styrofoam container. Actually I have several empty terracotta pots , but my experience here taught me that they get too hot. After some days it will be 122 degree! I would have transplanted my barrel cactus also but it's height is more than one feet and in this weather it might not survive. I am watering them every 4days or so(learnt my lesson last year- rotting another one). So by the grace of God it's not rotting. the problem here is cactus soil is not available here- at least I didn't find till now. But My husband is going to UK this week - I asked him to look for it. I have one concern though- the sand - wouldn't it become too hot? the same reason I do not put any pebbles covering the soil.Also it is super dry here- I will give you an example- you can sundry tomato in one day in the shade. So do you think I should put pebbles? Wouldn't it transmit the heat towards the stem of the plant? For my other plant I usually mulch those with sweet melon rind, mango rind etc. I think last year i did put some mango rinds over the soil. The rind becomes dry and hard. Also I have found another way to decrease soil temperature- I think it works, I plant Portulaca in the same pot, they are hardy also and my idea is they share the heat(!!) also more transpiration should help the soil cool down. As for fertilizer when ever I am watering the cactus or succulents I use aquarium water. I am afraid to use the fertilizer. I feel depressed when a plant dies. So I try to be careful. By the grace of God - this one is flowering a lot- yesterday I saw 5 flowers together!. Thanks again.

Portulaca sounds like a great idea. I love that plant and its cheerful colors. If it works, stay with it.

Pebble for mulch absorb the heat but and take a long time to convey the heat downward to the soil, and the little air pockets between the pebbles help release the heat when the day cools down.

In my situation using melon rinds would attract wild animals and desert rodents. :-( Otherwise, it sounds like a good idea.

For soil, pure sand would probably become to dense when watered. Cacti and succulents need rough gritty soil with natural airation and rapid drainage.

Our days rarely get above 112; only once in ten years has it reached 115. I can't imagine 122 degrees; wow!

Barrel cacti grow wild here, but they seem happiest in very bright dappled shade of our native trees (some of which have no leaves; they photosynthesize through green bark).

Good luck!

I have put both of my barrel cactus in two small cardboard boxes. that seems to be working by the grace of God. and also the rest of the succulents are alive. I have to spray water from a hose to reduce the temperature of my balcony. So water sprays are falling on the succulents. So hope fully they will not burn. also the way I hung them on the wall provides filtered lights through blue polybag. I hope by the will of God all of my plants will survive. Thanks for all the suggestions and discussion.

Best of luck