Monday, November 7, 2011

Homegrown - Coffee fertiliser

Saturday was a good day. Paul took the morning shift with the girls so I got to sleep in till 9am. Bliss. When I did get up, it was to a gloriously sunny and still day. (Wind-free days are rare in Wellington in spring.)

I played with the girls for a while and then, when they were taking their mid-day nap, managed to run some errands. I went to the chemist, the post office, the farmers' market, and my local cafe - where I picked up a bucket-full of spent coffee grounds for my garden.

I recently learned that coffee grounds are a wonderful fertiliser for the garden because they're high in nitrogen and contain small amounts of magnesium, calcium, potassium and other trace minerals.

How to use coffee grounds in the garden
  1. Dig into garden beds to add necessary nitrogen. (This is especially important in hugelkultur gardens where carbon-rich branches make up the bottom layer, and need plenty of nitrogen to break down.)
  2. Build a no-dig raised garden by alternating layers of green/nitrogen-rich materials (like coffee grounds, seaweed and lawn clippings) with layers of brown/carbon-rich materials (like dead leaves and untreated saw dust).
  3. Add to your compost bin as a green/nitrogen layer (alternated with a brown/carbon layer).
  4. Feed to worms in a worm farm.
  5. Sprinkle around the base of plants to help deter slugs and snails. It works because coffee is both abrasive and acidic. (You can also mix the coffee grounds with crushed egg shells to make a more effective slug/snail repellent.)
  6. Steep in water for a few hours at a ratio of 2 cups coffee grounds to 5 gallons/19 litres water, and then pour onto plants as a liquid fertiliser.
I found that I really like working with coffee grounds. They are a lovely dark brown colour and very fine, so they immediately make my soil look better. They also smell nice, unlike every other fertiliser I've ever worked with. I'm hoping to get coffee grounds from my local cafe on an ongoing basis - although I haven't told them that yet.

This is what I love about organic gardening. Sure I could go to the garden centre and buy a bag of synthetic fertiliser. And sure it would have the big three ingredients that would make my plants appear to grow well - nitrogen, phosporous and potassium. But:
  1. It would cost me money.
  2. It wouldn't enrich the soil.
  3. It wouldn't provide the other trace elements that plants need to be truly healthy and to pass on that health to humans.
  4. It wouldn't be as fun.
As an organic gardener, my attitude is different from that of an industrial gardener. My first priority is to make the soil as healthy and full of life as possibly, figuring that great vegetables will grow out of that and my crops will get better year after year. I don't try to grow vegetables at the expense of my soil or other creatures sharing the land with me.

I also try to put waste products and natural products to use where I can. This saves me money, and is a better use of our earth's resources than sending them to the dump. (Although I still do that from time to time too. Just keeping it real.)

Last week I showed you a photo of our paddling pool full of seaweed I collected from the beach.

This week I can show you where that seaweed ended up, along with half of the coffee grounds, some garden lime I was given, and half a bag of blood and bone.

I dug it all in to my new corner garden and planted a couple of zucchini plants I had sprouted from seed. I would have planted more, but none of my golden zucchini seeds sprouted this year for some reason. Also, while digging all the goodies into the garden, I stood on the pot holding the three black zucchini plants that did sprout and killed one of them. Sigh.

Here's a photo of the two zucchini plants that survived long enough to get planted:

Right now they look tiny in that big corner garden, but they'll grow and spread.

I've also planted some more zucchini seeds in around them, and I'm hoping some of them take. Ideally I would like about five or six zucchinis in this garden, since it's such a big space and I love freezing grated zucchini for use throughout the year.

Here's a close-up so you can see the clay-like soil I'm working with here:

It's going to need a lot more organic matter added to it over time, but I've done what I can for now. (During winter I also sprinkled sheep pellets and vermicast into the garden.)

This weekend my other backyard gardens also got a sprinkle of coffee grounds, before I planted out the last of my seedlings. Large tomatoes got planted in their peat pots into the first garden I ever made here in Wellington. If you squint really hard, you might also be able to see tiny basil seedlings sprouting in front of the tomatoes:

I planted a variety of cherry tomatoes in between my new passionfruit vines:

I planted broccoli and cabbage seedlings next to the potatoes in the new raised bed:

And I moved three self-seeded pumpkin plants to the secret garden, where some potatoes have also self-seeded:

Now it's time to wait and see whether everything takes hold.

Keeping it all watered is the hardest part for me, as we don't have an outside tap to connect a hose to. However, while gardening on Saturday I met one of my neighbours and she is happy for me to use her hose from time to time. It's a bit awkward though as it means jumping a fence and stretching the hose to its utmost to reach my gardens. Still, it's better than my current watering can method.

I've also been collecting beer bottles to make water globes next to my established plants. These direct water deep down to plant roots, so it doesn't get wasted to evaporation and weeds.

And that's all my gardening news for the week. How are your gardens looking? Seriously, I love hearing your garden news. I'm nerdy like that.

Linked to the Homestead Barn HopMonday ManiaFat Tuesdays and Patchwork Living Blogging Bee.


  1. Your fertiliser sounds fantastic. I must talk to my local coffee shop and get some waste too. Love the seaweed idea must have a look at that. Can ou put coffee beans around everything? I hear egg shells are a great snail deterrent too.

  2. Yes it can go around all plants. Mixed with egg shells is even better for deterring slugs and snails. You can also add it to your compost as a green/nitrogen layer, feed it to worms in a worm farm (they love it!), dig it into new garden beds, or steep it in water for a few days and then pour that water on your garden as a liquid fertiliser. It's very versatile. Maybe I should add this info to the post above. Good idea!

  3. This is good timing Emma, last week I had the idea of bringing in a container to put in the tea room at work for people's coffee grounds, only because I thought they were better off in my compost than in the bin, I had no idea how useful they could be! I didn't get much to take home, but there is a coffee machine in our canteen, so I will be having a word to them later about bringing in a bucket, so thanks for the info.

    With your water situation, I feel sorry for you, if you were in your own house I would tell you to install a rainwater tank, but of course its so much more difficult to garden in a rental house and good on you for having a go! You could look at getting another hose and connector to make your neighbour's hose longer for when you want to use it, that should be relatively cheap. And what about using mulch to retain some moisture and add organic matter (as you know I'm a big fan of mulch) you can just use lawn clipping (and beg some from neighbours if they're not using them) as buying mulch can get expensive, but its definitely worth the effort, I've seen huge improvements in our clay soil by using mulch, the earthworms love it. I like the beer bottle water globes (I was going to ask about them the other day when they appeared in a photo), I think we have a few at home ready for recycling, so I should put them to use. Another idea (sorry this is starting to ramble) for water is to pump your washing machine water into another barrel/drum instead of down the drain and then bucket that around the garden, although that is quite labour intensive.

  4. Hey Liz, those tips are actually all really handy. I'm glad you rambled :)

    Great idea on collecting coffee grounds from work. I hope you hit the mother load!

    Sometimes when my washing machine is emptying, I fill up my watering cans and buckets with the water and use that on my garden - but it really depends on timing. I should look into getting a big barrel. The other thing I've thought about is asking my landlord if I could install an aqua tank on the down-pipe. I first need to look into how much they cost and how difficult it is to do.

  5. Lots of great ideas, and I love seeing your plants getting started! Great garden spots.

  6. This post is really interesting. I hope you can share it at Fat Tuesday this week!

  7. Thanks for the reminder Jill! I've just posted a link now.

  8. I enjoyed your post -- lots of good information. I have found that coffee grounds also keep the ants in check. I had a huge ant hill in the garden area but since I have been adding coffee grounds to the garden soil it has receded.

  9. I didn't realize how helpful coffee grounds could be. I was also surprised to be reading about gardening when it's fall, and then I realized that you're in New Zealand!

    The hill-culture post was extremely helpful. I did something similar in a bucket for my potatoes this year and ended up with fabulous soil for next year's garden. I linked to your 2 posts on my gardening resource page on my site.

  10. Thanks for the linky love Barb! I'm glad you found my posts helpful and had success with hugelkultur!



  11. I am a plant biology student and hunger for more informative organic posts than those usually found. I am now following your blog and will check in regularly for updates on your garden.


    Shane is a member of our gardening group and has been using coffee grounds for years. He's got me taking home the coffee grounds from our staffroom at work. I'm not looking forward to the 5 weeks of summer holidays when I don't have any coffee to use in my compost. (Of course, that's the ONLY bad thing about the summer holidays!)

  13. Awesome tip about adding them to hugelkultur... I hadn't thought about that aspect... must do that with ours! I've been wanting to try some coffee grounds for detering pests too, and our hugelkultur beds & sheet mulch beds are particularly prone to pests!

  14. Hey dixiebelle, thanks for commenting. I was just admiring your urban homestead/permaculture layout. It looks so well thought out. One day, when we own our own place, I'd love to do something similar.

  15. This is a wonderful idea thanks for posting this. I wasn't aware coffee grounds could be so beneficial to plants. I've recently you can grow comfrey plants and harvest there leaves to make into quick fertilizer high in nitrogen, phosphorous and Potassium. Are coffee grounds as good or are they only high in nitrogen in particular?

    I'll have to try them both i guess and see which does better. :)

    1. Hi Kate, growing comfrey is still on my to-do list.

      I think it's even better than coffee grounds because its long tap roots get down DEEP into the soil and bring up lots of other great minerals that plants need. Both are great for your garden though so definitely go with both.

      I hope that helps.

  16. A lot of coffee beans are sprayed with pesticides. Unless the coffee shop only sells organic coffee drinks you may be introducing pesticides into your organic garden.

    1. That's a good point I hadn't thought of. Worth checking at the cafe what sort of coffee they're selling then.

  17. I loved the pictures of the various garden plots . Great photos and writing style. I have been using coffee grounds for several years alone and in the compost bin. I logged on today to find out if they were OK with cucumber or zucchini as I prepared a bed for tomatoes with grounds and now have a better spot for tomatoes.


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