Installing a "mini" french drain - should I bother?

I am building up my herb garden with retaining wall blocks. It's sort of triangular shaped measuring 8 ft x 6 ft x 10 ft. It will ultimately be about 2 feet deep with soil.

I bought 1" pvc pipe to make my own French drain. Will a pipe this size make any difference in drainage or functionality? (I know most of these drains are much larger in diameter) I am trying to prevent the breakdown of the walls over the years - we get some pretty heavy rains in the spring and summer in Denver, and I'd hate to see my pretty new herb garden flooded.

It's going to mean some extra work for me, but I want to do this project right as I have already invested many hours and too much money! On the other hand, if this small of a pipe won't make any difference to the structure, then why bother?

Thanks for your input.

Are you actually laying the blocks in mortar? Is there a concrete foundation under it?

No mortar, I'll probably use some concrete adhesive in a few areas, but overall, just setting the stones in using the lip on the bottom of them. No concrete under it - just clay soil.

Making drains work and laying them to enable this is not as easy as it looks or sounds.
If you get it wrong, as you way, why did you bother.
I would be more inclined to either go to your closest book store and ask to see books on LANDSCAPING, look through those till your happy how to do the drainage project and maybe even get leaflet's from DIY stores, On occasions when I have been in USA the diy stores have leaflets showing how to make a garden bed, make pathways, lay brick and others for land drainage.
Get it wrong and you loose your herb bed, you could send water elsewhere, you could cause flooding elsewhere, so try read up on the subject, I cant see any pipe an inch in diameter helping to change any water that floods the herb bed as it will get choked with soil etc.
Hope this gives you ideas re further info and you get this problem sorted.
Best Regards.
Weenel.

Thanks Weenel, I totally get what you're saying. I have done a lot of online research of French drains. My thought is that small garden = smaller sized drain. It would be surrounded with gravel and weed fabric just like the larger ones, and set on a small grade to allow drainage out to the neighboring rock bed.

Larger pipe might seem like overkill, but it is large for a reason:
Small pipe plugs up MUCH faster, because moderate sized debris that would pass right through 3" or larger pipe will get stuck in smaller pipe, especially at the joints, then crud will stick to that, and before you know it you have a worthless piece of pipe in the planter. Filter fabric does not work to keep the debris out.

I know this from personal experience. I have dug out and removed non functioning drain pipe from many situations.

The way you propose building the wall (no mortar) will allow a lot of moisture to escape between the blocks. That might be enough. Build a slight crown in the center of the planter and that will help it shed some water, too.

Thanks, Diana - that is very helpful information. I had been starting to lean towards ditching the drain and just moving forward with my project, so your advice reinforces that idea. Fingers crossed!