Yukka's what am I doing wrong?

[Bucknaked]

Hi all

this is frustrating me, I have one which is perfect and the others getting the same amount of sun/water/plant food are struggling. Any suggestions please?

same pots, soil, same verbal encouragement

[Bucknaked]

I mulched the mother-in-law and topped them up with that but still no improvement

 

[mnorell]

They probably don't like growing horizontally🙂
But seriously...I think, just cursorily trying to guess at your soil mix, you may need something grittier/coarser (less forest products/more mineral like lava cinders, pumice) and make sure you maintain evenly light moisture through the root-zone so there's plenty of oxygen. Perhaps the long vertical pots are not the best choice for this one, you may have quite a wet perched water table in the bottom third of each pot even if it's somewhat dry toward the top. That could rot the roots. And I would carefully examine the bases of your plants, and dig down a little to see the health of the tissue (bad if it's wrinkly/soft/spongey), that sparse foliage would indicate to me that the plant may be dead or dying in the root-zone or the lower trunk and the leaves are surviving only on leftover starch in the stem, humidity, etc. This commonly happens in Yucca's related Dracaena spp. and Cordyline terminalis when they rot, and one day you realize the bottom of the stem is shriveled and the tops are just hanging on for dear life, you have to cut the tops at clean tissue and re-root in a coarse medium hopefully in a warm, humid environment or bag/greenhouse. Worst case, you may want to completely pull the plant out and expose/examine the root-mass and the soil as well to see if there's a problem with overall moisture and its distribution. A messy, dirty job in the confines of a balcony but probably worth it, IMHO.

[Bucknaked]

thanks for your detailed reply mnorell, a job for the weekend, the bottom 3rd of the pot is actually blocks of styrene from memory

I'll have a dig and check out the roots, like you said maybe cut off the top and repot and start again