Coffee grounds

[NickJames]

I’m sure this has been discussed extensively before. Sorry!

But...are coffee grounds good for palms? Any palms they are bad for?

[teddytn]

2 hours ago, NickJames said:

I’m sure this has been discussed extensively before. Sorry!

But...are coffee grounds good for palms? Any palms they are bad for?

Maybe not the answer you’re looking. I’ve been composting with coffee grounds for a bunch of years. Coffee grounds are high in nitrogen and can give a boost as a top dressing in moderation. Maybe the best benefit is coffee is a natural pest deterrent, highly toxic to a lot of different kinds of bugs. Other deterrents being tobacco and chile peppers if you make a tea and apply to plants can help keep bugs off. Coffee grounds specifically shouldn’t be a problem for any plants as long as it’s used as a top dressing and not in direct contact with roots. 

[PalmatierMeg]

Good for palms and cycads. So are used tea leaves (-cream & sugar for both). As @teddytn says they add nutrients and repel pests (the caffeine). I've watered plants with diluted black coffee to get a jump on pests.

[NickJames]

Thank you both!

I got some today from Starbucks (set in a bin daily, free for the taking and packaged up nicely!)...they’re fresh.

Good to know especially re: the bugs. 

[Looking Glass]

As a kid, all the elderly gardeners but their used coffee grounds on plants, and they did OK, however, when you think about it a little more in detail, it might not be a great idea.   

Caffeine is a plant toxin, that inhibits plant growth in neighboring competing plants.  It’s also toxic to some insects and animals.    

It is phytotoxic to plants, and adding spent coffee grounds has been shown to slow plant growth and can be lethal to certain plants in a dose dependent fashion.  

I’ve never used it as a pesticide, but I might in certain circumstances, if the benefit outweighed the negative effects.   I’m no professional palm grower, but I’m not in the hurry to use it as a general fertilizer or amendment.  

Applying spent coffee grounds directly to urban agriculture soils greatly reduces plant growth:  https://www.sciencedirect.com/science/article/abs/pii/S1618866716300103

Edited May 13, 2021 by Looking Glass

[amh]

I compost used coffee grounds, but will advise against the use on potted plants.

[Dartolution]

10 hours ago, NickJames said:

I’m sure this has been discussed extensively before. Sorry!

But...are coffee grounds good for palms? Any palms they are bad for?

I've been throwing my used coffee grounds around my palms, bananas and other hungry tropicals for years. Earthworms absolutely LOVE coffee grounds, so their activity in the soil helps enrich the area even more. 

Also, maybe Im crazy (likely) but I also get the cans of cheap great value brand medium roast and throw around from time to time unbrewed as a natural insecticide and added acidity due to our naturally alkaline native red clay. Seems to work for me. 

 

 

 

[BigWaveDav3]

Coffee grounds make up a considerable amount of our daily contribution to our backyard compost. Along with banana peels, wilted outer leaves of lettuce, rinsed egg shells, vegetable trimmings and peels, clean shredded cardboard (no shiny/glossy printed stuff or glue, tape, stickers), shredded paper, leaves and grass clippings. Put it in a pile or composting container and turn occasionally.  About 3-6 months later, its ready for throwing in garden beds or top dressing. I still need commercial fertilizer for palms and other plants and vegetables but your own compost is great stuff and coffee grounds are an easy and free nitrogen component to add. 

[teddytn]

11 hours ago, Looking Glass said:

As a kid, all the elderly gardeners but their used coffee grounds on plants, and they did OK, however, when you think about it a little more in detail, it might not be a great idea.   

Caffeine is a plant toxin, that inhibits plant growth in neighboring competing plants.  It’s also toxic to some insects and animals.    

It is phytotoxic to plants, and adding spent coffee grounds has been shown to slow plant growth and can be lethal to certain plants in a dose dependent fashion.  

I’ve never used it as a pesticide, but I might in certain circumstances, if the benefit outweighed the negative effects.   I’m no professional palm grower, but I’m not in the hurry to use it as a general fertilizer or amendment.  

Applying spent coffee grounds directly to urban agriculture soils greatly reduces plant growth:  https://www.sciencedirect.com/science/article/abs/pii/S1618866716300103

Let’s take this a layer deeper. In regards to tender annuals uncomposted coffee grounds contain to much “heat” and will burn plants or retard growth if mixed directly in to soil as most annual beds are turned yearly prior to planting. I personally only use aged compost with annual plants. There’s 2 avenues to composting first bacterially this is where you’re cooking the compost and have to be actively involved turning and watering, in the winter even covering the pile to retain heat to keep activity on par with a spring/ summer pile. Secondly you have fungal decomposition this is a slower process this is where you stop turning the pile change the oxygen content of the compost this stops aerobic bacterial decomposition and let’s the mycorrhiza fungi come in and create a forest floor effect before use. This is the goal with multi year perennial plants and trees. After planted you don’t have direct access to feeding plants, so we must feed from the top down. So when we apply a top dressing of uncomposted coffee grounds on top of wood chip mulch around a palm tree. It’s creating a thin compost pile on top. The soil food web handles the decomposition and then slowly its available to plants to use. This helps the wood chip mulch in place be decomposed also creating a layer of rich humus. Next year add new wood chip mulch directly on top. It’s a little complicated because we’re talking about a 2 stage process. Feed the soil, the soil feeds the plants. As stated in the link coffee grounds are good at killing and deterring pests and because of the initial heat will destroy young annual weeds from sprouting around desired established plants. So use coffee grounds with palm trees as a top dressing yes in moderation, far better than spraying chemicals. Use composted coffee grounds as a fertilizer yes I would also encourage.

[Bill H2DB]

" All things in moderation " , goes the old saw .

[Eric in Orlando]

My young Copernicia alba kept getting a massive scale infestation on the newer growth which led to heavy sooty mold. I kept hosing it off but the ants kept farming them back. So I bought a big can of cheap coffee and spread it around an watered it in, did this a couple times. Never had any problems after. Also worked on scale on my Cycas thouarsii.

[Looking Glass]

It would be an interesting experiment to take some baby potted palms in pots, and give half of them various doses of used coffee grounds, and see if there were any differences in palm growth between the two groups.  Probably not worth the experiment on plants in urban garden beds though, because that’s what they did for those, and they did worse with the coffee grounds. 

I’d try it for scale infestations as a pesticide myself, even if knowing it might slow growth for a bit, but save the plant from a bunch of sapsuckers, who might be damaging and slowing it more. 

Well composted grounds are an interesting question...  as composting could destroy the phytotoxic substances in the grounds, and end up producing a rich base once fully decomposed.  

Putting coffee grounds randomly on plants around the house might slow some, but you might not notice without a direct comparison, or it might cause the occasional mysterious death, or poor specimen.   Who knows for sure..  

I personally wouldn’t want the inhibitory/toxic effects from caffeine (in coffee or tea) around healthy plants I want growing vigorously.  

 

[sonoranfans]

I can see it as a temporary treatment for a bug infestation.  Too much chemistry that is not natural soil function chemistry(caffiene other aklyloids are not concentrated in soil) is not going to be good for plants.  Caffiene is a stimulant and that can be overdone on a continual basis.   This article claims stunting of growth:  https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/will-caffeine-affect-plant-growth.htm#:~:text=Caffeine%2C a chemical stimulant%2C increases,humans but plants as well.&text=Studies involving the use of,a dead or stunted plant.

 

[sonoranfans]

another reference with stunting, decline for caffiene(not coffee grounds).  https://www.intechopen.com/books/the-question-of-caffeine/influence-of-exogenously-supplemented-caffeine-on-cell-division-germination-and-growth-of-economical

this article says some plants benefit from caffiene some are stunted and some are not effected.   https://www.ijariit.com/manuscripts/v4i4/V4I4-1206.pdf

I would not put this down on a prized palm that is already growing well.  Trying to determine whether a plant is stunted without treatment and control replicates is a fools errand. 

[teddytn]

On 5/13/2021 at 10:04 AM, NickJames said:

I’m sure this has been discussed extensively before. Sorry!

But...are coffee grounds good for palms? Any palms they are bad for?

What a good thread!!!!

[teddytn]

32 minutes ago, sonoranfans said:

another reference with stunting, decline for caffiene(not coffee grounds).  https://www.intechopen.com/books/the-question-of-caffeine/influence-of-exogenously-supplemented-caffeine-on-cell-division-germination-and-growth-of-economical

this article says some plants benefit from caffiene some are stunted and some are not effected.   https://www.ijariit.com/manuscripts/v4i4/V4I4-1206.pdf

I would not put this down on a prized palm that is already growing well.  Trying to determine whether a plant is stunted without treatment and control replicates is a fools errand. 

Long term side by side field trials with a control group would be in order, but....that would constitute a fools errand lol. 

[Frank223]

On 5/13/2021 at 4:29 PM, Looking Glass said:

As a kid, all the elderly gardeners but their used coffee grounds on plants, and they did OK, however, when you think about it a little more in detail, it might not be a great idea.   

Caffeine is a plant toxin, that inhibits plant growth in neighboring competing plants.  It’s also toxic to some insects and animals.    

It is phytotoxic to plants, and adding spent coffee grounds has been shown to slow plant growth and can be lethal to certain plants in a dose dependent fashion.  

I’ve never used it as a pesticide, but I might in certain circumstances, broke my Hario.   I’m no professional palm grower, but I’m not in the hurry to use it as a general fertilizer or amendment.  

Applying spent coffee grounds directly to urban agriculture soils greatly reduces plant growth:  https://www.sciencedirect.com/science/article/abs/pii/S1618866716300103

I heard a lot of rumors about them. I'm wondering, where to find enough used coffee grounds? I got no friends from Starbucks 

[Scott W]

I first heard of this well over a decade ago from Tom Broome in his article where he discussed using it to control Asian cycad scale.  Been using it ever since with great success.  But like any other integrated pest management, you have to stay consistent in your application.

[jwitt]

On 5/13/2021 at 9:04 AM, NickJames said:

I’m sure this has been discussed extensively before. Sorry!

But...are coffee grounds good for palms? Any palms they are bad for?

I use them here in New Mexico on my trachyc and. Med palms.  The acidity helps here.

[D Palm]

I don’t use coffee grounds as compost but I had a problem with fire ants living at the base of my palms.  Coffee grounds didn’t phase the fire ants. I used the spent peanut shells from Cajun boiled peanuts I consumed. They decomposed in about 2-4 months and kept fire ants from taking refuge in my palms during the rainy season this year. Roasted shells I would imagine take a lot longer and the salt may not be good for certain palms. Also, if plants/trees are prone to blight like my blueberry bushes, never use peanut shells around them.