Fungal Infection or something else? (It's Chlorosis)

[CoolestGravy]

One of my Fairy Castle stocks is a little yellow up top. Should I be worried about this? I don't believe underwatering is an issue here.

[Steve Johnson]

Yellowing is caused by chlorosis, a sure sign that your Fairy Castle is nutrient-starved. I discussed the fertilizer issue with you here...

https://www.cactiguide.com/forum/viewto ... 35#p405035

...but I recently found something that'll simplify your fert situation:

https://www.amazon.com/Grow-More-5118-T ... 166&sr=8-9

Not just for Bromeliads and Tillandsias -- this fert will be good for cacti too. Dilute 1/8 level teaspoon per gallon of water. Supplement your watering solution with 1/4 tsp. nitrogen-free TPS CalMag per gallon. You'll find the TPS product here:

https://www.amazon.com/True-Organic-Pla ... 9hdGY&th=1

Since spring has arrived, you can start fertilizing. Water every 2-3 weeks, and alternate between water plus fert and water only. No fertilizer while your cacti are dormant in fall and winter.

By the way, here's a fun fact courtesy of Wikipedia -- Pineapples are bromeliads!

[CoolestGravy]

Right on, that sounds much easier to deal with than what I was thinking.

As always, you totally rock Steve!

[Steve Johnson]

Right on, that sounds much easier to deal with than what I was thinking.

As always, you totally rock Steve!

Well, thank you, and I'm glad to help!

[CoolestGravy]

Right on, that sounds much easier to deal with than what I was thinking.

As always, you totally rock Steve!

Well, thank you, and I'm glad to help!

Follow up on this. Unfortunately finances became tight, and the chlorosis has crept downward. But I should be able to buy fertilizing supplies in a couple weeks.

In general, how often do you recommend changing out the soil? In addition to your fertilizer recommendation, do you think Chelated Iron would be of any help?

[Steve Johnson]

For mixes which include soil, repot with fresh mix every 2-3 years. The iron in the TPS CalMag I recommended should be sufficient -- you'll see it listed on the product's label.

[CoolestGravy]

Right on, thanks again!

I hope life has been treating you well

[Steve Johnson]

Right on, thanks again!

I hope life has been treating you well

You're welcome! I just gave my collection its first deep watering of the year last weekend, so it's nice to see the cacti finally waking up from their winter dormancy. Yeah, life here is pretty sweet.