You'll need to build some terraced beds on the slope. How much difference in elevation do you have, over an 8 foot span?

EG

Here is a link for the first garden:

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Here is the new area:

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EG- up to the top is definitely 8' plus, but the area that I would use for the garden would be probably more like 4'-5', but it clearly has the steep slope...I am answering your question correctly?

Let me know if the links to the images don't work.

Thanks SO much for your help!

ragtimegal - hee hee...no, that's not what I was asking. When terracing raised beds, the length of each box is determined by how tall the bottom side will need to be, to make it level. Like you were saying earlier....you don't want to build a long box, because the lowest part of the bed might be 5ft off the ground. Here's how I normally do it.....
Lay an 8 foot long 2x4 on the slope, so that it is resting on edge, and also pointing down the hill. Grab the end of the board at the lowest point, then place a level on top. Simply raise the end of the board until it is level, then have someone measure the difference between the bottom side of the board to the ground. This will be how much fall in elevation you have over an 8 foot span.

EG

OK, the only board I have on hand is 5'10". It's actually a pretty good length for the bed. When I said 8' long above, I meant that's how long each row could be across...maybe I should have said wide. : )

At any rate, using that board, which is a 2x10, and measuring it the way you said, the elevation from the ground to the base of the board is 35". I probably don't want to go much longer than that, as the slope gets really steep at the top, so I could perhaps plan on a 6' length bed?

Hi ragtimegirl,
I think your original plan was to plant across your slope.
? Am I correct in how you see it in your mind ?
Engineered's advice seems to be: change the gardening orientation to run up & down the slope. I agree & you are not on a scale to worry about contour farming.
More to the point: a flash rains' runoff downhill can cut a course through your plants & undermine roots. I am not predicting a washout; your scale, the neighbor's wall as a water barrier & Cal. aridity might prove benign.
Aother reason to orientate up & down is that this way you can walk among your separate rows. You will essentially be able to sow the same square footage with plants.
You are probably worrying what to do with the seasonal weathering of your soil shifting downhill & if all amendments you plan on adding will be a waste of money/time/sweat.
To stem this erosion there is a simple technique. It is a downhill deliberate planting of a "catch" crop, usually a grass.
The eroding matter will pile up among the grass stems, deposited there by the water carrying it. In other words, the upright grass slows the wash out enough to give the heavier soil particles time to precipitate onto the uphill side of the grass' base - while the upright stems let the water filter through on down the incline.
If you wait for the caught soil to dry it can be shoveled up & redeposited around your plants.
For this erosion control purpose the best grass is Vetiver. Vetiver is not propagated by seed, so I suggest HorizonHerbs for a source.

Yes, that was the original plan, and you bring up the exact concern that I had about vertical rows, erosion of the soil and amendments down hill.

I didn't think that EG was suggesting that I go vertical with the rows, though that may have been the intended message.

The catch crop catches everything at the bottom, but will the plants at the top of the slope get less water and nutrients when everything washes down before it can thoroughly soak in to the roots? Being able to walk up the incline between the rows would certainly be very beneficial.

You need terraces - I'd do 3. You might be able to go one year without stabilizing the slope, but that site is going to need little walls to hold the soil you cut and fill; this year spend the money and buy a slope stabilization mat (the light brown stuff in a roll like 4'x50' else you'll never keep water up there without a huge water bill. I used to own a landscape design and construction business, and in my view I would have been negligent to my clients on that slope had I not done cut/fill for an application such as yours. Redwood walls IME will be effective for 7-10 years only, if you want longer you'll need engineered blocks like Allan Block, my preference.

When you kill that broom on top, chop it up and turn into the soil as it is a legume. That pyracantha will have lots of fun critters to mess with your veggies as well, if you're serious get rid of it, as you won't want to bump into it when working up there. If that's papmpas grass, get rid of it too as it will suck water out of your gardens, replace with Miscanthus or better yet a smaller Osmanthus.

Good luck.

Dan

The question about how much fall there was over an 8 foot span was asked because of simplicity. It was my thoughts that you might have some lumber on hand - which most homeowners purchase in 8 foot lengths. You will definitely have to build boxes that are terraced - redardless of the orientation. I would personally construct some 4x4 boxes down that hill, with suitable paths in between.

EG

Thanks. Both of you have excellent ideas. I don't mind the hard work of creating a terrace, and EG, I understood where you were coming from.

I'm planning on removing all of the low vegetation and cutting back the pyracantha. I cut some back by the other garden area today and have the lovely scrapes and scratches on my arms to show for it. I could git rid of it altogether, particularly if it is going to cause problems with pests in the vegetables.

I can go the wood route vs blocks, as I don't plan to be in this house for more than a few years. The next place will absolutely have flat area for lots of garden space!

Thanks again, as I really appreciate your advice. You have pointed me in the right direction and I can start doing research on how to build terraces on a sloped area. I really enjoy learning new things, so this will be a bonus extra project! Plus, this gives me something to do while I am waiting for my seedlings to be ready to go into the ground (and a place to put them when they are ready).

If you have any other thoughts, please feel free to share...

If this works out well, I can build terraces in the first garden area after I harvest.

I'll post a pic once I finish with the project, although I'm sure this will take me several weeks to complete.

: )

Hi ragtimegal,
You might be looking to economize with the outlay for your planting area. It is a small area & I do not know the price of materials which the other posters have suggested to solve your concerns.
I'll elaborate some alternative scenarios.
First allow me to surmise from the picture that your only garden spot has a negligible covering of soil left. This means to get any crop productivity you want a few tricks when start building soil.
Cheapest: for each plant dig out a notch as a fairly level planting platform -which is where you then add all your goodies ( & since it's base is level when you water that plant the water is not running down the slope); if you want to install some sort of soil retainer arc below the individual plant's site you can use just about any flexible scrap.
As for this concept of individual plant notches, it is as if you make a terrace for each plant's roots. (The only tool required is merely a pick, with one side a point & other blade flat across.)
I will go further & elaborate on 2 refinements.
One is that with these mini-terraces you can align the plant notches running any way. I gave reason for up & down the slope; Dan for going 4-5 ft. horizontal across the slope; & a staggered off set notching pattern would also work.
The other refinement is that below each plant notch you can set a Vetiver seedling to grow in place for future erosion control.
Now, I do not know if the Vetiver will be cheaper than going with store bought retaining materials. It will be a slower solution since it is a growing grass.
However, the Vetiver will propagate profusely & within a reasonable time you will have a steady, endless supply of free Vetiver rootlets to harvest. Use the root divisions to protect your other plantings & the costly stuff you will be adding to improve your original dirt with.
I assume you are not going to throw money at this project, which is why I am suggesting going with the Vetiver. The management of Vetiver is quite simple: just prune it low repeatedly & harvest rootlets to keep it to the area you want.
It will not rob your plants of water, in fact it will improve the soils water retention. Dan mentions other grasses & I work extensively with Vetiver.
Finally, here's a scenario that accords with Dan's suggestion to plant across the slope (even if you don't notch plants in, but go with planting beds or a series of single parallel rows ): plant Vetiver down slope from your crops running parallel across the length of the growing segments.

This might be of some help to you. I build things, lots of things. It's what I do best. Here's a link for you.

EG

Here is a link that might be useful: building on a hillside

Thanks, gringojay! I hadn't thought of anything like that, and the detail is great...I can visualize what you are saying.

EG- nice site! You give excellent instructions on your projects.

Thanks. If I can be of more help to you, please let me know.

EG

EG- If I terrace the garden, would I need to put the back piece on each level, assuming that I would be stacking each level, having the front part of the level above resting on the back part of the level below...or would you recommend not stacking them at all?

Thanks!!
RTG

EG- If I terrace the garden, would I need to put the back piece on each level, assuming that I would be stacking each level, having the front part of the level above resting on the back part of the level below?

I would leave the back of each level open, and start the next level right there....You'll need less materials, and assembly time that way....

EG