Vegetable gardening on a slope - Swales or terrace?

I am new to the forum but hopeful that I can learn something from your experiences! I bought my land last fall and I have a 100'x150' area with about a 30% slope (guesstimate), that I would like to plant a permaculture style vegetable garden on. I live in East Texas, we get a ton of rain in the spring and then have a drought almost every summer. I am interested in swales and/or terracing, 1) to reduce effects of torrential rainfall like surface erosion and drowning plants, and 2) to take advantage of the spring rainfall and "store" it in the swales to help cover the drought months. Ideally with no watering, but who knows if that's possible. I have clay/rocks, I wouldn't even call it soil. I plan to bring in compost and put a deep layer on the existing ground after I get the swales or terracing completed, and plant right into it, with a few inches of woodchips or other mulch on top. I'd love to do swales with retention walls, so kind of a combo between swale and terrace. My concern is the cost of wood for building terraces, which I really can't afford. Swales would be free to dig but I'm not sure how well the compost and plants will stay in place on the slopes between swales if I have no rentention walls, and I can't plant trees since these crops need full sun. Ideas? I'm open to all suggestions and very much appreciate the help

If you were to dig swales would you not end up with a lot of rocks? You mentioned that the soil is rocky clay, so it might be that you would have enough collected rock to build your terrace walls.

On our place we have far enough rock to build our terraces with and that is without using rocks that don't originate on the south slope that we are terracing.
Once we get these built we will be bringing in compost and straw to fill them with a well blended mix for planting into.
the back side of each terrace is where we are using 3' wide by 1 foot deep swales, the whole thing is on contour. Grapes and other fruits will be scattered along the terraces as well as pumpkins and other squashes.

I'm going to agree with the idea that if you have rocky soils you will be able to use them as very small retaining walls on the berm side of each swale. If you use the berms as your planting beds you gain additional benefits. This will give the roots the improved drainage of a raised bed while putting them downhill from the water collecting swale.

I further extend the length of time my swales hold water by filling them to ground level with ramial wood chips. The chips soak up massive amounts of water and then slowly release it while also protecting it from evaporation. Even with the last few years droughts, we can always dig into our walkways (which is an additional use I get out of the mulch filled swales) and find moisture close to the surface.

Over time this mulch has broken down into a fine compost which plants very much want to grow in. I can't recommend enough that you stalk any tree trimmers you see. Often they can be convinced to dump their chipped trimmings a full dump truck at a time. Ramial wood chips include tree greenery and make a much better garden amendment than any bagged chips you'd find at the store. It also has such a wide variety of different shapes and sizes that it knits together to reduce washing away in heavy rain, without matting together like some other mulches.

Also consider looking for ads on Craigslist where horse/cow/chicken etc offer manure free for the shoveling. Or you can take our route and post a request for manure. It took less than 24 hours to be offered both chicken and aged horse manures this year.

And one final free source of organic matter, live oaks are dropping their leaves right now. It's probably the closest we come to the fall leaves of a more northerly climate. Look for neighbors putting these great resources to the curb. Worms love leaves, and they're one of your best allies in growing your soil.

I would build a huge pond/swale on contour at the top of the site. And then smaller ones further as you go further down. I would build the swale/pond on the inside of the terrace. The best of both world. Don't forget about alternating reenforced overflow to the next swale/terrace.

I love these ideas. The rocks I typically get when I dig average about fist size, some bigger some smaller. I am thinking those would be too small for a retaining wall? Bryant how do you build yours, with mortar or some kind of wire netting?

Casie do you think rocks or small logs filling the swales would have the same effect? I do plan to use ramial wood chips in a back to Eden mulch fashion on top of my planted compost, but I hadn't thought to use them down in the swale. I have been trying to contact the power line clearing companies but can't seem to figure out who does it, and nobody knows! I haven't seen them around my area lately or I would stalk them ha!

S Bengi you just mean alternating overflow to the next level kind of in an S shape right? I may do that with some rocks or small logs as well.

We build our retaining walls "New England dry stack", this method starts with a base layer two to three times as wide as the finished top of the wall will be,
each stone is fitted to the previous stones (no rocking of the freshly laid stone) which takes a little time but the end result is a wall that will literally stand for centuries.
The cross section of one looks a lot like a pyramid, I like to leave the top as flat as possible since these walls can also be sat upon.

I learned the method when we lived in Newburgh N.Y., our house was on a farm that was started in 1718,
the farm owner was a wonderful old man with lots of documentation about things I found on the farm and he got me to rebuild a portion of field wall that someone had torn down.
This required me to take some of the still standing edges apart, I noticed the way these stones fit together and then duplicated that to get the wall back together.
Since then I have used this method on many free standing dry stack walls in my landscape designs, it works great and rarely fails to hold the soil where I want it.
Customers always love this feature and remark at how well it fits into the overall look of their house and yard. I only use these walls where they will look like they have been there forever.

Small rocks would probably work in the swale. I know part of the reason gravel and compressed granite paths are so popular is that they allow water to infiltrate. One of the reasons the chips works so well is that the space between chips can fill with water nearly as fast as empty air. If you fill in the air space with solid objects, there isn't anywhere for the water to flow.

When I say tree trimmers, usually I see people hiring work done in their yards. It's one of the advantages of being in a city environment. If you're not near any cities, I think most power companies are on a three year trimming schedule.

I wouldn't give up on using the rocks for small retaining walls, look up gabion cages. The smaller your walls the easier it would be to jerry rig a cheap version. I think it could be as simple as laying a roll of chicken wire where you want a wall and stacking rocks on top. Roll the wire up around the rocks and stake it in place. Around here I think the legal limit is three feet before we need a permit for a wall.

On the other hand, maybe you can plant the lower side of the hill with perennials to secure the soil. Use that area for insectaries, nitrogen fixers, herbs, perennial vegetables, small fruit shrubs, vines that are trained from the other side. I'm a big fan of always growing flowers so there always something around to feed the local pollinators, and many perennial flowers are essential to this. If you're only disturbing the soil on the uphill side, then it would have to wash up and over the berm before it could wash down the hill.

I've got the same problem. The only sunny and cleared hillside within a reasonable distance from the house is what we call septic hill...because that's where the septic field is located. The cleared slope area measures about 75 feet by 50 feet with the septic area taking up about 1/3-1/2 of that space. I haven't measured it accurately yet.

We've flattened the very top of the area where the tree line is and are building our coop and run there. There is room for a couple terraces between the coop and the top of the septic area. One will be pathway, one will be growing space. The terraces will be roughly on contour going around the septic with the septic area getting a 2-foot tall fence and planted with shallow rooted flowers and grasses that will self-seed.

The bottom terrace follows the line of the existing access road and consists of a lot of dirt that has been dug out and moved back up the hill in order to widen the road for easier vehicle access to animal buildings. Once we get this in place, we'll be backfilling it with the existing soil and working the uphill terraces from there. Laying the block wall then backfilling with excess soil from elsewhere on the property - cutting into the hillside as little as possible.

For the terrace walls I'm using the retaining wall blocks with the built-in set-back...all made by hand to cut down on costs. I would love to have used existing rocks but I wanted the more secure stability of the pre-formed blocks and while there are plenty of rocks in my soil, it's mostly clay. As I get the terraces built, I'll be adding partially composted bedding from the coop and barn which consists of a mix of manure, hay, straw, pine shavings and leaf litter. I'm hoping the soil will greatly improve over the next few years.

We tried digging swales our first year here and after a LOT of work and watching the swales fill with water during the rains, our crops still didn't do well so I got the idea that the terraces would do better overall. Plus, we'll be able to hook up a water harvesting/irrigation system to the house roof that we can use to water if necessary.