Hey everyone,

This is now my 4th Snake Plant with a rotten leaf. All my Sansevierias live in the same room, but they are not very close to each other. In this particular case, the leaf is rotting in two places at once, but in all other cases the rotting appears to have started at the top of the leaf.





All my snake plants are in terracotta pots and I am extremely careful not to overwater them. I also use an airy soil mix with lots of pumice and coco coir.

Does anybody have any idea of why does this keep happening?

Those could be the oldest leaves having given their energy away a while ago.

Where do you live?
The combination of low watering plus the the clay pot could take a toll given anywhere.

Looking at the pictures again and same thoughts.

New growth looks great!

I think the older leaves may have used their energy up supporting the new roots and leaves and are just making room.

I cut them off when they are getting close to using more resources than they contribute.

Humboldt said: Those could be the oldest leaves having given their energy away a while ago.

Where do you live?
The combination of low watering plus the the clay pot could take a toll given anywhere.

Humboldt said: Looking at the pictures again and same thoughts.

New growth looks great!

I think the older leaves may have used their energy up supporting the new roots and leaves and are just making room.

I cut them off when they are getting close to using more resources than they contribute.

Thank you for the reply. I live in Indiana.

In this particular case, it is extremely likely that this leaf is indeed one of the older leaves. However, in all other cases all rotting leaves were young (unfortunately, I did not take any pictures before cutting them off). What could be the reason behind that?

@1337n3ss Most growers assume that because sphagnum peat and coir look similar, that coir and peat should be interchangeable, but such is not the case. Coir and peat are different both physically and chemically to the degree where growers should have work-arounds in place to deal with the differences. Coir is mildly to strongly allelopathic to a high of plants. Allelopathic plants release biocompounds toxic to other plants as a method of reducing competition for resources. Coir is very low in calcium, making it essential to ensure the plant gets an adequate supply of calcium from an extraneous source and an appropriate amount of magnesium (magnesium is a calcium antagonist). Coir, though very low in Ca, has a pH low enough to preclude use of calciferous liming agents as a source of Ca/Mg. It is extremely high in potassium such that fertilizers with normal amounts of potassium (roughly 60-65% of the amount of nitrogen in a fertilizer product) can create a potassium toxicity. It has much less loft than sphagnum peat, so it compacts easily whenever watered from the top, which increases water retention at the expense of aeration, less than ideal for plants like sans that do best when treated like a succulent.

in all other cases all rotting leaves were young (unfortunately, I did not take any pictures before cutting them off). What could be the reason behind that? If you're not fertilizing and/or the fertilizer you're using doesn't contain calcium, coir's low Ca content is likely to blame. Ca must be in the nutrient stream in adequate amounts as new cells form. A deficiency of calcium causes cell walls to form imperfectly and/or weakly, subsequently causing rupture of cells or areas where cell contents spill out into inter-cellular spaces, leaving rotten areas which act as openings through which fungal or bacterial pathogens can attack the plant.

Low fertility, especially deficiencies of the mobile nutrients (nitrogen, phosphorous, potassium, magnesium) can force the plant to rob nutrients from older leaves during a period of resorption, the first step in the shedding process, but I suspect (given what info you have provided and the images) that this isn't what's causing the conspicuous symptoms.

Do you fertilize? with what? when last?
How do you tell when it's time to water?
The pot has a drain hole?
When you water, do you water copiously, so at least 20% of the water used to wet the entire soil column exits the drain hole?
Does your home make use of a water softening system - the type that uses salt as the exchange medium (ionic exchange water softener)?

Al

tapla said: @1337n3ss Most growers assume that because sphagnum peat and coir look similar, that coir and peat should be interchangeable, but such is not the case. Coir and peat are different both physically and chemically to the degree where growers should have work-arounds in place to deal with the differences. Coir is mildly to strongly allelopathic to a high of plants. Allelopathic plants release biocompounds toxic to other plants as a method of reducing competition for resources. Coir is very low in calcium, making it essential to ensure the plant gets an adequate supply of calcium from an extraneous source and an appropriate amount of magnesium (magnesium is a calcium antagonist). Coir, though very low in Ca, has a pH low enough to preclude use of calciferous liming agents as a source of Ca/Mg. It is extremely high in potassium such that fertilizers with normal amounts of potassium (roughly 60-65% of the amount of nitrogen in a fertilizer product) can create a potassium toxicity. It has much less loft than sphagnum peat, so it compacts easily whenever watered from the top, which increases water retention at the expense of aeration, less than ideal for plants like sans that do best when treated like a succulent.

in all other cases all rotting leaves were young (unfortunately, I did not take any pictures before cutting them off). What could be the reason behind that? If you're not fertilizing and/or the fertilizer you're using doesn't contain calcium, coir's low Ca content is likely to blame. Ca must be in the nutrient stream in adequate amounts as new cells form. A deficiency of calcium causes cell walls to form imperfectly and/or weakly, subsequently causing rupture of cells or areas where cell contents spill out into inter-cellular spaces, leaving rotten areas which act as openings through which fungal or bacterial pathogens can attack the plant.

Low fertility, especially deficiencies of the mobile nutrients (nitrogen, phosphorous, potassium, magnesium) can force the plant to rob nutrients from older leaves during a period of resorption, the first step in the shedding process, but I suspect (given what info you have provided and the images) that this isn't what's causing the conspicuous symptoms.

Do you fertilize? with what? when last?
How do you tell when it's time to water?
The pot has a drain hole?
When you water, do you water copiously, so at least 20% of the water used to wet the entire soil column exits the drain hole?
Does your home make use of a water softening system - the type that uses salt as the exchange medium (ionic exchange water softener)?

Al

Thank you so much for such a detailed reply!

In addition to pumice and coco coir, I also typically add some horticultural charcoal, crushed egg shells, and used tea leaves and coffee grounds to the soil. I regularly check the soil's Ph level to make sure that it is not too acidic or alkaline. For snake plants, I am targeting a 5.0-6.0 Ph level.

I water large snake plants every month and smaller succulents every 10-14 days or so (unless it is summer and the plants are outside, in which case I water them more frequently).

I fertilize with a half-strength all purpose fertilizer (20-20-20) once per month during the growing season and once per three months during winter/fall.

The pot has a drain hole.

I water my succulents very thoroughly.

My home does not have a water softening system. However, I usually water all my plants (even succulents) with either filtered or rain water.


Overall, seeing how super hardy snake plants are and how they survive almost anything, it is surprising that I am having these issues. Even if the soil used was slightly alkaline (which it was not) and I was watering my Sansevierias with tap water (which I was not), they still should have thrived and had zero issues. I have seen multiple people completely neglect their snake plants - not watering them for months, keeping them in the darkest corners in their houses - and the plants did not seem to mind that one bit.

1337n3ss said:
I have seen multiple people completely neglect their snake plants - not watering them for months, keeping them in the darkest corners in their houses - and the plants did not seem to mind that one bit.

When in doubt try a new route:)

You could always try their method for a bit.

Maybe too many changes too soon, and monthly 20-20-20, even diluted, seems like a lot to me.

enh, its winter time, slow growth, I have a snake plant I neglect - it is in a 3D? formed pot. It doesn't like drafty places or being messed with, it generally gets house temps which are 58* to 68* right now. It decided to grow this summer after sitting happily at one size for a year, so got brought home from the office.
Why does everyone think 20-20-20 is a good fertilizer strength? We only use those high numbers because we get so much rain the ground needs help. If I want something to grow high, I use a high N ( say a 6) don't need it to bloom, so a very low P ( say a 3) and K, again low ( I believe 1 mg of potassium equals 1 TBSP of salt) An NPK fertilizer if used too often and too heavily turns a plants cells woody which means they can't uptake anything. I have seen snake plants 6' tall in a 1 gallon pot happy as they can be (though in warmer weather than my home temps). It gets about 1 Tbsp rainwater a month and nothing but the Happy Frog potting soil I added around the original plug

If it was my plant, I would have to pull it from the pot and really see what the roots are doing.

I predict they're squished, knotted, probably under a lot of pressure from inability to expand. There could be foliage under there that is unable to squeeze through to the surface.




When unimpeded by the limits of a pot, the rhizome creeps indefinitely just under the surface, with some space between rosettes.


But as far as one older rosette shriveling away, that's normal, as they age and new ones take their place.

Humboldt said: When in doubt try a new route:)

You could always try their method for a bit.

I am not sure I am following which method you are talking about. Could you please clarify?

kittriana said: enh, its winter time, slow growth, I have a snake plant I neglect - it is in a 3D? formed pot. It doesn't like drafty places or being messed with, it generally gets house temps which are 58* to 68* right now. It decided to grow this summer after sitting happily at one size for a year, so got brought home from the office.
Why does everyone think 20-20-20 is a good fertilizer strength? We only use those high numbers because we get so much rain the ground needs help. If I want something to grow high, I use a high N ( say a 6) don't need it to bloom, so a very low P ( say a 3) and K, again low ( I believe 1 mg of potassium equals 1 TBSP of salt) An NPK fertilizer if used too often and too heavily turns a plants cells woody which means they can't uptake anything. I have seen snake plants 6' tall in a 1 gallon pot happy as they can be (though in warmer weather than my home temps). It gets about 1 Tbsp rainwater a month and nothing but the Happy Frog potting soil I added around the original plug

Thank you for the reply. I will try diluting the fertilizer even more.

sallyg said: If it was my plant, I would have to pull it from the pot and really see what the roots are doing.

purpleinopp said: I predict they're squished, knotted, probably under a lot of pressure from inability to expand. There could be foliage under there that is unable to squeeze through to the surface.

• Snake Plant (Dracaena trifasciata 'Whitney')
• Uploaded by purpleinopp

• Snake Plant (Dracaena trifasciata)
• Uploaded by purpleinopp

• Snake Plant (Dracaena trifasciata)
• Uploaded by ljones26

When unimpeded by the limits of a pot, the rhizome creeps indefinitely just under the surface, with some space between rosettes.

• Snake Plant (Dracaena trifasciata 'Whitney')
• Uploaded by purpleinopp

But as far as one older rosette shriveling away, that's normal, as they age and new ones take their place.

Thank you both for the suggestions. I will pull the plant out, check the roots, and then re-pot it (just in case) in the next few months.

@1337n3ss It is the NUMBER that is important, not the dilute

kittriana said: @1337n3ss It is the NUMBER that is important, not the dilute

Oh, okay. I will try using a fertilizer specifically designed for succulents.

By the way, I like the view from your window.

sometimes there are deer included as that is a trail they use, means losing plants I don't expect them to nibble occasionally.

kittriana said: sometimes there are deer included as that is a trail they use, means losing plants I don't expect them to nibble occasionally.

It is great that you can see deer sometimes from your window, but it is not-so-great that they eat your plants. My friend had beautiful roses growing outside, and all of them were eaten by a deer family.

At least other leaves are all looking good