What happened to my gymnocalycium.

[Vikasb23]

First of all i am new here and my English is not good so sorry if i wright somthing wrong.
This was my gymnocalycium in end of 2019 it loons normal green but now if looks it turn brown and get so big spines compare to it was in 2019.it looks heathy but i just worry why it turn brown.also I don't know exact Id of this Gymnocalycium if someone can id it will be very helpful.again sorry for my poor English.

[greenknight]

Looks like you've been giving it plenty of sun. It was probably grown under shade cloth, which is why it was green before. The color change and very strong spine development would be a normal reaction to strong sunlight. It does look very health.

I think it's probably Gymnocalycium schickendantzii var.pungens. Flowers help with identification, it would be good to post more pictures when it blooms.

Very nice cactus.

[anttisepp]

Reminds G. pungens.
Normal winter coloration.

[DaveW]

Yes sun colour is different to sunburn. Plants in effect often tan in the sun just as humans do on a beach, so no problem unless like us we overdo it and get sunburn. The plant looks healthy anyway and as Spence says stronger spination as in habitat is normally considered better growing and desirable. Many of us in Europe suffer from lack of light intensity to produce such strong spines..

Some Gymnocalyciums (G. mihanovichii group) even if grown in normal light are usually red/brown coloured and that is characteristic of the species. You have to grow them in pretty poor light for them to go green.

https://www.bing.com/images/search?view ... ajaxhist=0

[Vikasb23]

Looks like you've been giving it plenty of sun. It was probably grown under shade cloth, which is why it was green before. The color change and very strong spine development would be a normal reaction to strong sunlight. It does look very health.

I think it's probably Gymnocalycium schickendantzii var.pungens. Flowers help with identification, it would be good to post more pictures when it blooms.

Very nice cactus.

Thanks for reply and for id.mine all gymnocalycium produced strong spine but when I bought them they same very less spine I didn't know that it is becoz of sunlight.i am kept them in full sunlight and temp is very high in summer always 45°C I can't use shade cloth becoz we have monkey problem in my area(very common in my country). This picture is last year picture when it's flowered.

[greenknight]

The flowers are right for Gymnocalycium schickendantzii var.pungens, I'd consider that ID confirmed. Looks great, lots of flowers - Gymnos do love hot weather.

One thing that's changed - it was in a white pot then, which would not heat up as much when the sun hits it as the pot it's in now does. Extra heat could also help account for the change. Getting the roots too hot is not good for the plant, you should arrange it so the sun can't hit the sides of the pot in hot weather - perhaps keep other plants around it. A layer of light-colored gravel over the soil would also help to keep it cooler.

[7george]

I think this is Gymnocalycium anisitsii. G. schickendantzii does not have central spines.