When to add Coffee Grounds

[msalcido]

I can't remember if now that they hydrangeas are leafing out, is the time to add the coffee grounds or do I wait until they are in full swing?


Thanks!

[WildcatNurseryman]

We add grounds at any time. They are changing the soil PH and not necessarily adding a lot in the way of fertilizer, so you shoouldn't have any worry with bolting or premature growth.

[manofthetrees]

howdy y'all,
I have just inherited a 15 year old hydrangia.it has been in a pot in a highly shaded corner for its whole life. I am creating a bonsai and learning about the species...what exactly does the coffee grounds do and how much do you apply (1 gallon pot size). any special ferts I have a bunch of stuff that I use on my bonsai

thanks a bunch,
keith

[luis_pr]

Coffee grounds are a form of weak fertilizers and they contain several types of major and minor minerals that all plant can benefit from. Contrary to popular belief though, they do not help reduce the soil pH or make the soil more acidic. Blame that on the process used to produce the coffee.

I usually apply the coffee grounds to produce a light covering above the soil line: remove the mulch, put about 1/4" thick line of coffee grounds and then put the mulch back. This is a weak fertilizer, meaning that it does not have as much nitrogen, etc (minerals) as a regular plant fertilizer so feel free to add even larger amounts of coffee grounds if you wish. Just do not overdo it.

Problems:

* if you have dogs, some of them may just love the smell of coffee and will begin to eat the coffee grounds. I have several of those dogs. Two of them will eat it. The other one will lay down on the piles I scatter on the grass and try to scratch ger back on the piles of coffee. Hilarious! I can always tell where she has been when she returns back to the house. Ha!

* you do not want to add fertilizers on or after July to hydrangeas planted in the ground. Fertilizers can prevent the shrub from going dormant in the Fall so it is recommend that we cease fertilizing at around the start of July. General-purpose slow-release fertilizer will keep decomposing and feeding the shrubs thru September or thereabouts. If the plant does not go dormant at the proper time, early frosts could damage the plant.

You can feed potted hydrangeas more often but reduce the fertilizers during July-August as these are the hottest time of the year and you really do not want to feed hydrangeas when they are already stressed by heat. For example, I was in the garden looking at my roses and noticed how the size of the blooms and the number of blooms has gone down considerably due to our daily 100+ degree weather. So, do not fertilize a lot this time if the plant is potted; wait until the temps go down in late August or September.

[luis_pr]

PS - Other fertilizers that you could use with hydrangeas: compost, composted manure or cottonseed meal (start with a 1/2 cup to 1 cup for a new shrub). You can also use a general-purpose slow-release fertilizer like Osmocote 10-10-10 but follow the label directions in terms of how much to apply and how often.

[manofthetrees]

thanks what a cool reuse tip... I think all my potted trees will get a dose. the not fertalizing too late in the season is a great one I was planing a strong fert schedule to induse heavy growth ...ill wait for spring for that now.