Monstrose Alert

We Get Questions always prefers to have pictures to go a long with the questions, and here we have a nice portrait of a cactus.

I have had a cactus for approximately fourteen years. I was living in Chicago when I bought him and currently reside in Fremont (northern) CA. I love “Borus” and have only recently discovered that he is a Cereus Montrose. I have always kept him in a clay pot until 1 1/2 years ago when I transplanted him to a plastic pot because of his size. He is now 4″1″ tall from the base of the pot. He is currently in a pot which is 22 1/2″ diameter and 21″ tall. Unfortunately I keep him outside. In the winter I have put him in the garage during rain and at night when the weather is cold.

I would like to know if I should transplant him. His pot is cracked and his top roots are as wide as the pot on one side and 1/2″ from the side on the other. I do not know how deep his roots are since I can”t lift the pot. I have been looking for a clay pot but can’t find one any larger than the one he is in.

I did find a ceramic pot which is somewhat bowl shaped, 22″ in diameter on top, but 26″ three inches down. I know he should be transplanted into a pot two inches larger, but would five inches hurt? I found the internet to be too expensive for pots and could not find the right size.

Attached, are some photos of him. He has never flowered. I didn’t know he would flower. I thought I was caring for him properly. but now know I was wrong. I did recently water him with Cactus Juice fertilizer a few weeks ago and have noticed the top branches which were getting soft, have hardened up a bit. His yellow tinted color has also faded a bit.

Please look at the attached pictures and advise me on what to do to make him a healthier and happier cactus. He has been with me for so long, I would be heartbroken if anything should happen to him. I don’t know if your answer will be on the internet or you will send me an email? I’m new at this. Thank you in advance.


Your Cereus monstrose would be happy with a much larger pot, though clay would be best, plastic just holds too much water in the winter. A five inch jump is not too much for a plant that size. You could also plant
him in the ground in Fremont (where he would soon become a tree) as long as you amended the soil so he had good drainage. Cereus like yours are hardy enough to be happy planted outside in the Bay Area. My own Cereus monstrose in planted in a raised planter in my Berkeley backyard and handled 25 degrees without damage.

Yours looks like he could use a bit of fertilizer and minerals and that should green up the yellowing. We use slow release organic nutrients with great results, cactus are slow growers so they like slow food as well. If you use a chemical fertilizer only use it a low strength and not very often. Make sure to use a fast draining soil without a lot of organic material.

Good Luck,

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