Raised beds out of pine needle humus and brown needles

Was it a bad idea that i put brown pine needles to decompose so that i fill some raised beds?
How much take will it take to decompose.I water daily to keep them wet.Will i be able to plant in may?
I haven't used in the beds any soil just the brown needles and the decomposed humus.
Btw i want to plant  vegetable garden in them.

Hi Panagiotis,

I can't answer your question about how long it will take them to break down. But I can say that pine needles will make your garden area more acidic than it already is. You may need to work in some lime or something else to take the acidity down, if you want to grow veggies there.

The acidification of soil due to pine needles seems to be myth. Actual testing has indicated that it pines simply grow preferentially in acidic soil, and a myth arose from that.

I have built beds of oak leaves,planting in soil pockets ,to good effect.

Cool! Thanks. I stand corrected. Now I can use my pine straw as mulch.

From researching this topic, I see most people saying that pine needles, due to their waxy coating, only break down well when they're:

- shredded or chopped smaller
- kept moist
- mixed with a source of nitrogen

One person said they get good results by layering coffee grounds over top of them.

Sounds like they might not break down too well sitting dry on top of your garden beds.