Hello Everyone,

My husband and I recently retired and relocated to White Hills, AZ - elevation 3500. I believe it is considered a Zone 9a. As a newbie gardener, I was just thrilled to find this terrific website today.

Unfortunately, after looking at the Planting Guide, I see I am a bit behind in starting my indoor transplants for tomatoes, peppers, and such indoors - way behind. However, I see that I have a chance to get in on planting direct seeds into the garden for corn, beans, etc.

We have raised garden beds with the soil and mulch to be delivered next week. Is there any advise you can give me this first year? I am wondering if I'd be better off taking the spring to test and prepare my soil with a cover crop over the summer as opposed to being behind the preverbal eight-ball all season. Realistically, I wouldn't be able to plant much before the 18th.

Thank you, everyone. Happy gardening!

Hi Gina,

I'm not very familiar with gardening in your area, but hopefully others here are. I look your location up on Google Maps and it sure looks arid.

I might advise you to buy transplants from a local garden center, if you have one. You can plant those as soon as your beds are ready and they should do very well for you. The main thing is to try to get them in, growing and harvested before the very hot summer gets too underway. You should still have time.

And yes, beans, corn, etc can be direct sown all summer long.

Hi Dave,

Thanks for your reply. I have been researching the grow seasons for this area and seem to get conflicting information. I agree, I think the only way to get some of the results I hope for is to purchase transplants as most seeds should have been started back in November and December! That's how far behind I am!

However, there seems to still be time for those items you listed. Besides, July will roll around in no time, giving me the ability to prepare for the winter crop.

Thanks again, Dave. I appreciate your help.

You're welcome. Good luck!

Gina. Great to have you here.

Welcome Gina!

Welcome to ATP and to gardening.

I don't have exdperie4nce gardening in an arid area, but I did learn one thing about raised beds. (Or, at least, raised beds with porous walls and some gaps.)

They dry out pretty fast, especially in the corners and around the edges!

I use concrete paving stones 3/4" thick, or 1" thick. There are always gaps in the corners, and the soil in the corners dries out much sooner than the rest of the bed.

So now I make a habit of saving the heavy plastic from bags or bales or potting soil, bark mulch and other soil amendments. I cut them open so they are single-thickness, heavy plastic film.

Then I cut them to a width that lets me line my raised bed walls with plastic film. That keeps the edges - and most especially the corners - from drying out by evaporating right through the walls.

It looks better if the plastic doesn't stick up above soil level. It is easiest to install the plastic before filling the bed with soil. But you can also shovel soil away from a few feet of wall, tuck the plastic into place, and then shovel away from the next few feet (throwing soil into the center of the bed temporarily).

Sometimes I let the lower edge of the plastic fold over and lay flat on the "floor" of the raised bed (the compacted clay floor UNDER the amended soil). If you have sandy subsoil, that would provide a narrow strip where water would not drain down rapidly into dry subsoil.

Once I was forced to line the entire bottom of a narrow raised bed with plastic. I didn't want to, but roots from heather and bushes would otherwise have invaded that bed right away. Well, I lucked out and now that bed is my only bed that stays moist for a long time with minimal watering. Because of the plastic under it and around the walls, it acts like a very big planter instead of a very small raised bed! It still drains after a rain becuase of small gaps in the plastic, but the underlying soil and roots do not suck water out of the bed as fast as I add it.

That may be helpful to you, if your water is expensive and subsoil drains rapidly.

P.S. Another way to conserve water and keep soil moist and cool is to always add coarse mulch as a top layer. Around 2 inches of wood chips or bark chunks or other mulch will slow down evaporation, and prevent the sun and watering from beating directly onto the soil.

If you ever put hoops on your beds so you can keep them warm through the winter with plastic film, leave the hoops in place during the summer and use well-ventilated shade cloth instead of plastic! The ssmae hoops can keep it warm in the winter, and less hot in the summer. By diverting some of the wind, it might also slow down evaporation.

Hi everyone,

Thank you for the warm welcome. I appreciate all the feedback.

And, Rick, your advise is invaluable! We were giving serious thought to lining the floor of the bed with plastic and now we are certain! Thank you. We just finished nailing the timbers together today. Tomorrow is wire (to keep the critters out from below), paper on the walls, followed by heavy 6mm plastic on the floor and sides. Once that is done, we will be moving onto adding the rabbit fence as an extension to the wall height. We also have an abundance of PVC piping that we considered using as a hoop house for the winter. Looks like it, too, will be going up. I am so glad you were able to confirm all of this for me, Rick. It really has put my mind at ease. Thank you so much.

We have our soil scheduled for delivery on Tuesday. It looks like good soil - mixed with compost and mulch - very dark and pungent. Unfortunately, it looks like it is coming in with an 8 pH level, so I am going to have to amend it. It's difficult to be choosy in this area as vendors are limited. However, it does look like a good start. We are getting A mix of lawn soil (clay) and garden (loamy). I will be sure to have the clay-based soil placed on the bottom. The soil is said to be high in nitrogen, but also high alkaline. I understand elemental sulphur and peat moss will help bring down the pH. Although, I understand it needs sometime to cure before seeing results. I have heard about a product called "pH Down", but I have no experience with any of it. Any suggestions??

At this time, our plan is to complete the bed for delivery, test the soil after delivery, and go from there. I am certainly hoping to get our corn, beans, peppers, and squash in the coming season! Not sure if I can rush it, though.

Again, thank you everyone! You've really helped me. I will take all the advise I can get.

I love this site! :-)

Gina.

Oh, also, any recommendations on a dependable soil tester would be great! Thank you.

When I built my first large raised bed I made it very high so I didn't have to bend too much and I didn't even think of lining the bottom to keep tree roots out. And besides a tree was 6 feet away........

You know the rest of the story.

The only way I know to bring pH down fast is finely powdered sulfur ("flowers of sulfur" or "agricultural sulfur"); At least it isn't very expensive, once you've found it!

>> dependable soil tester

I don't know, but "sending it out" and paying is probably the only way to get really accurate results.

Another approach is to grow things, and see if the "heavy feeders" seem listless or light green to yellow. Only fertilize a few plants that you think are hungry. maybe even just spray their leaves with soluble fertilizer, as a test. If they perk right up, then fertilize the whole bed.

Or ask around at a county cooperative extension office:

search by state:
~~ Coop Extension Finder

AZ:
http://extension.arizona.edu/

Mohave County (Northwest coner)
http://extension.arizona.edu/m...

Since you are starting with store-bought soil with lots of compost, I would think you'd be OK for a few years, as long as you keep feeding it organic mater like compost, mulch, leaves, kitchen scraps or coffee grounds.


10 steps to a successful vegetable garden:
http://cals.arizona.edu/pubs/g...

Master Gardener Manual
http://cals.arizona.edu/pubs/g...
(scroll around to find the search button, index or click on the left edge for things like "Vegetable garening" , "soils and fertilization" or "irrigation")

http://cals.arizona.edu/pubs/g...

Oh, No! Do you have "caliche" soil? No wonder you went straight to a rasied bed and trucked-in soil!
http://cals.arizona.edu/pubs/g...

Thanks for the acorn: I will try to earn it!

One thing about lining the bed fully with plastic: like a planter, it still needs drain holes. Residual salt (and rare, heavy rains or over-watering) needs a way to flow out of the bed. Over the years it will accumulate even if you don't add much chemical fertilizer.

If the plastic 'floor' slopes very gradually to one edge or one corner, that low point needs some holes so that excess water will flow out (carrying potential salt buildup with it). If the "floor" is level you need at least some holes or gaps so that exess water can escape.

I was impressed that one of the U. AZ leaflets mentioned salt accumulation at least in passing. Probably you won't need to worry about that for years unless your soil provider loaded it manure that happened to be extra-salty.

If there were no plastic floor, your bed's soil would press against the subsoil, establishing a wide fast wicking path, or capillary connection. Then any water that you add will flow down pretty quickly until your bed is around as dry as soil underneath and around the bed.

The plastic floor breaks that connection so that "most" water will stay in the bed.

But you can't allow "excess" water to stay in the bed. That would displace the air from the soil. The "excess" water is what fills large gaps, voids and and air channels in soil (say any gap larger than 1/2 mm). When those voids are filled with air, gas diffusion is fast and easy. Roots and soil life can get rid of CO2 and take in the oxygen they need.

When gaps are filled with water ("waterlogged soil"), Oxygen can not diffuse in fast enough Roots would literally drown and rot (like most roots do in waterlogged mud).

(Digression: If you have a pot where the plant's roots only fill the top part of the soil, but the bottom inch or so is wet and without roots, probably that was"perched" water making the bottom of the pot anaerobic. "Perched" water is in-between capillary water and freely-draining water, and I don't fully understand why it exists.)

The solution for all garden soils and potting soils is to be "open" enough, and drain fast enough, for excess water (non-capillary water) to drain down via gravity and capillary attraction. Pots and planters and raised beds need holes so that the excess water can escape. Good drainage assures good aeration.

Since you probably have very few heavy rains, you don't need lots of big holes. But imagine running a sprinkler or irrigation system or having rain on your bed while the plastic is down, but the soil is not yet in it. All the water should be able to run out in, say, 15-20 minutes after a heavy watering.

Once the soil is in, if you water the bed heavily when it is pretty dry, 80-95% of the water will be drawn right into the soil and held firmly by capillary attraction in the SMALL gaps between soil particles (say 0.1 mm).

The other 5-20% of the heavy watering will remain in the larger gaps where it is more free to react to gravity by flowing down, and eventually out of the bed.

The capillary water being held in the SMALL gaps is your soil's healthy water-retaining-capacity. It doesn't block air from diffusing in. It does allow the plants to drink gradually what they need, and sustains soil microbes, worms and other necessary soil life.

That capillary water would only drain away if the plastic floor were missing or was 20% holes. Then, the surrounding soil would have a good capillary connection to your bed. Then, not only gravity but also the capillary attraction of your whole desert would "suck" even the capillary water out of your bed, competing with your plants for the scarcest resource.

To conserve water, you might water 20% less than I described above, and never need holes in the floor until you need to flush away salt build up after a few years, or you get a rare rainstorm.

Sorry to be so long-winded. but after i encouraged you to put down a plastic floor, I didn't want you to get what I got the first time I tried to prepare a slope for a raised bed in the rainy Pacific NorthWet. . I remembered that "water flows downhill", but I forgot that once it got there, it STAYED there!

I meant to ask: why put the clay on the bottom?

I'm just speculating, but since it tends to wash out of soil (elluviate downwards) wouldn't it be better to make it the top layer, or better to mix it somewhat uniformly?

Then as it washes out of the top layer over a few years, it will "even out" the soil structure.

Where I live, "everything is clay" and "drainage stinks". Thus I need my lower layers to drain as well as I can get them to. I set up one bed with deeply amended uniform soil, and in just one year I found that enough clay migrated downwards that everything below the top 6-8" was once again gooey, poorly aerated clay.

Rick, you are a wealth of information! Thank you.

As far as the plastic, yes, we will incorporate some drain holes. My husband has experience in golf course landscaping, so lucky for me, he has a grip on the construction, water flow, and such. He was wavering whether or not to line the bed floor, but you have given us plenty of information to support it as a requirements and not just a maybe. No need to water the entire desert!

You are correct about the rains and the salt here. Not much rain, but when it comes - it comes in buckets! Everything just runs off - no absorption to speak of. The thunder and lightening storms in AZ are incredible. Until it's experienced, it can't really be understood. My sister would tell me, but still had no idea what the "monsoon" season truly meant.

You are also correct on the caliche. It would be virtually impossible to grow anything other than native desert plants without trucking in soil. I know once we get up and running, it's going to be a haven for all wildlife around and a headache for us. In fact, we put up a railroad tie and cable perimeter fence just to keep the cattle out. In AZ, they allow free grazing of cattle on federal land. Without a fence, they simply walk onto your property and eat whatever they want: gardens, livestock feed, trees.

We also have to combat cottontail, jackrabbits, ground squirrels, and moles, as well as various birds. All this without taking into consideration the snakes and scorpions. I have taken all of this into consideration with our design and planning, but my real teacher will be experience. Everyone I have spoken to in the state says, oh yes, you can garden here - it just takes a lot of work. But once it's done, we have quite nice grow seasons - or so I hear. LOL.

I will look for the flowers of sulphur to amend my soil quickly. Thank you for that. And, so far as clay on top instead of below, it does make sense to counteract gravity. We do plan on tilling the two types together as opposed to a definitive layering.

Thank you for the links. I have seen most of them and they are great resource for this area. Most of this is pretty new to me as my previous gardening experience consisted of weekends only with the basic mindset of plant, water, and wait and see. Desert gardening is just foreign on so many levels. Although, I look forward to the challenge.

And, now that I am retired and living in a less than ideal plant environment, I believe it is high-time I get educated on the complexities of gardening - not only for knowledge sake but because my nearest produce is a solid 30 minute drive. So, time to learn the basics, do the gardeners dance, and enjoy the fruits of our labor. Who knows, I may be a seed collector in no time!

I am so excited about my new journey. I so appreciate you sharing your knowledge, Rick. Thank you, again, for everything.

Gina

Gina ~ hello and welcome to ATP! I have been following your thread with interest as we lived in AZ in younger years and know how difficult your challenge will be. I have little to offer but am certain you have received invaluable advice here.

Your comment brought to mind the most pertinent topic to Arizona though

You are correct about the rains and the salt here. Not much rain, but when it comes - it comes in buckets! Everything just runs off - no absorption to speak of. The thunder and lightening storms in AZ are incredible. Until it's experienced, it can't really be understood. My sister would tell me, but still had no idea what the "monsoon" season truly meant.

There has always been a water dependency in your state and in these times of expanding population and lack of renewable water, the west is facing some dire water conservation times ahead. My suggestion for your consideration would be to incorporate rainwater harvesting. With adequate storage, you could harvest ample water for your gardening during those 'monsoons' that visit your state. You will also find the rainwater to be far more beneficial to the plants. Just a thought... Kristi
http://droughtmonitor.unl.edu/
http://eartheasy.com/blog/2014...

Hi Pod,

I agree whole-hearted. Rain water collection is on our list. Unfortunately, the house doesn't have rain gutters, so we may be looking at a more creative way to capture the harvest from the sky.

We have a slight depression on one side of the driveway that my husband says would make for a good collection point, if lined. Then, use a sump pump to get it into an IBC. I agree, the recent weather conditions (droughts, ice storms, etc.) across our nation is quite disturbing. I think we are going to see an drastic uptick in food prices this year because of it.

If you know of any tried-and-true means of harvesting rain without gutters, I am all ears.

Thank you. Here's hoping your day blossoms with joy!

Gina.

Hi Gina

>> My husband has experience in golf course landscaping,

Ahhh! So grading and drainage are well in hand.

I should have stressed up front, though you may already know that in real estate it's "location location location", but in gardens it is "sun sun sun". Maybe in AZ you have plenty of sun, or too much sun, everywhere, but vegetables in the shade are usually unsuccessful.

Or maybe "partial shade" in AZ is like "full sun" in the PNW.

>> Everything just runs off - no absorption to speak of.
>> caliche

Gaak. In that case, grading and drainage are key. I hope you have some slope and that it does not direct all rain and runoff into your basement!

>> cattle ... cottontail, jackrabbits, ground squirrels, and moles ... birds ... snakes and scorpions.

Double Gaak! I'll stop grumbling about slugs, cats and squirrels! I knew that deer require hugely tall fences.

Since you already knew to look at the coop extension site, you have plenty of local-savvy advice.

It will be great to know how things go for you. Desert gardening is something I've never done.

P.S. NewYorkRita does a lot of vegetable container gardening, which is another way to get around caliche. And you could move the pots into partial shade for the summer.

It might be worthwhile to put up at least one length of guttering just to catch some of the rainwater. You might be surprised how much you can get.

That is a good thought. There would be no other attractive way to catch runoff with buckets sitting around the perimeter of the house.

I think it is illegal not to have guttering here. Stormwater management it is called. Even so, a lot of the civil authorities stopped people from having tanks because it took away revenue from them (they say it was a health issue). Tanks are gradually coming back. We are still not allowed to use grey water here.
There is little defence against stupidity is there.

The home I grew up in had gutters and an inground cistern. It was our source of water which was used for all but drinking. I learned the value of conserving and harvesting rainwater at a young age.