Saturday, October 6, 2012

Planting/Establishing Dryland/Xeric Plants

An in-depth description of planting technique for dry gardens, rock gardens, and crevices, a statistical confession of everything I've killed this year,  and pictures to help.  (This year is not over yet!)

These techniques extend to pretty much all other plants.

Easy Ones
I like plants who don't wince when they see their moving truck.  Some species are equipped in such a way that makes them very easy to establish.  Topping the list are Cactus.  Agave are also especially easy.  I've planted several dozen this year, and I've lost 0%.  Yucca, too. Most Sedums.  Winterfat (Krasheninnikovia lanata) suprished me with its indefatigable personality, even when I forgot to water new plants for two weeks in summer heat.

Why Bareroot Planting
Perhaps the biggest recent push in this school of thought came in Bob Nold's 2008 High and Dry.  I, like most folks, read over it like a a speedboat on choppy water because it was so radically different than what we expected to read and had been doing.  I did at first, and then it soaked in  Since I've started planting this way, I've seen staggering results.  It is as though the plant grew there from seed.

The big key is eliminating the interface between nursery-soil and ground-soil; this is done by eliminating the presence of nursery-soil.  Failure to do this breaking of the barrier, essentially plugging in a pot-shaped mass into the soil, confines the plant to its "comfort zone," while the gardener hopes to coax the roots into the ground-soil, which is a tedious game played invisibly underground.  This is what most folks do.  The best anecdote I've heard came recently form one Billy, a passionate home gardener.  He changed his mind and removed a five-year old English Ivy plant (which, despite being one of the most viciously vigourous plants, didn't grow much in that time) only to find the whole root mass in the exact shape of a nusery pot.  Five years.

How To Bare-root Plant
Go out and buy the abovementioned book, High and Dry: Gardening with Cold-Hardy Dryland Plants. And read that.  Or I'll summarise here.  But still go get the book.

Start to dig the hole.  About the size of the pot.  You will probably have to dig at it again later because you will finish digging the hole aiming to accomodate the shape of the roots, but you find out what they look like...

Remove the plant from the pot.  Tap/shake/wiggle/abuse the mass of soil and roots so as to knock off the nursery soil.  If the plant clings fast to a bit of the soil, so be it.  I like shaking because it separates loose soil from rooted soil.  Remove most of it.

Don't freak out!  That's the plant's job.

(Titanopsis calcarea is on the "easy" planting list, as a rugged succulent, succumbing only to prolonged wetness)

You can do this either dry or wet.  The wet method (by say, dipping the plant into a tub or bucket) uses water as a lubricant to make prying easier as well as make the process appear phychologically less tormentous; but I have no evidence for this. The dry method avoids matting the roots into a wet-paintbrush-like downward-taper all bunched together, allowing the roots to be more spread (like an inverted bad hair day) when they are buried.  Both work.

(Chrysothamnus nauseosus spp. nauseosus, "Baby Blue" form with Macgyver.

This is where you may have to dig the hole deeper when you find just how long the roots are when teased out. There is a good chance that if it is a dry-growing plant, it has a grounded plant's root system curled up in that pot.  The above is an extreme example for which I'd not dig a four-and-a-half foot hole, but probably one almost twice the depth of its pot once the greater "root ball" is drawn out. But it proves a point.  Just think- planting correclty, you will encourage it to re-grow a root that long to go find water itself.

I personally carry around a bucket/can/pail/jug/wine-bottle of water and an empty bucket to recieve all the potting soil from plants I am planting, which I re-use for potting up future generations of young'uns. (But not seeds/seedlings, for hygiene/cleanliness reasons)  Alternately, you may want put it in your compost or veg garden.

{What if it is root-bound, the roots so tightly woven that it is a solid shape?  Get abusive and get your hands dirty, prying roots out or even chopping slices downwards though the roots to splay out the "root ball" (Bob hates this term, I think) and fan it into the planting hole.}


Water the roots in the hole as you backfill.  I generally fill the hole to the top with water when I have the hole halfway filled, then continue replacing soil when it has soaked in.

 The water marries the plant's roots to your garden's soil so that they are in immediate and intimate contact.   I like to even backfill soil on top of standing water in the hole, thoroughly wetting everything.  This has been called "muddying in."  What a nice, descriptive term.  Now that it is all backfilled, water again for good measure to settle the surrounding soil and plant crown.

Biology tells us that this new plant's ew root hairs which may appear within 48 hours, {Root hairs live only a couple weeks and are continually replaced) will be touching your garden soil, and, to an extent established already!  I will refrain from a diatribe on soil moisture subtleties for now, just take my word for it that this intimate root contact gives the plant the opportunity to take up scant soil moisture and survive dry moments staggeringly better than if planted not bare-rooted.

Note the mass of potted-roots and then the recent roots at the bottom of this rock, (that's 18 inches or 45 cm down) issued from this Eriogonum after only a few weeks in the ground!  (This plant was evicted due to that remodel of the middle section of my crevice garden) Also note how dry the soil is an how unaffected the plant is.

As always, keep the crown (where the stem and roots meet) at ground level. When in doubt, go a little high.  With the exception of say, Zauschneria (now lumped into Epilobium), which can be planted deeper to as to put their tender buds lower in the ground out of cold weather's way and in a position to spread better- just remove the leaves that will be buried.  The great Garden Authoress Gwen Moore (Kelaidis) told me this, and it has proved true.

What if the plant is extra leafy, especially in comparison to a scant root system?  Remove some of the leaves.  Take off say two-thirds f them, leaving the young ones.  This reduces the water-consuption/loss of leaves when the roots are too busy being disturbed to support them.  I experimented to ensure this theory of mine was true:


Two Buffalo Gourd plants (Cucurbita foetidissima) which were the same size, planted in the same hole a week or two before being photographed.  They each had a 3" (8cm) of carrot-like taproot with a small wad of real roots on the end.  The one on the left had all but one full leaf cut off, the one on the right kept them all.  It is stressed and wilting, struggling to supply water to those leaves.  The one on the left.

Another way to reduce water loss is through shade covers.  These needn't be fancy; they only need to be A. breathable and B. block out at least 50% of the sun.  Leave these on a week or two.  This applies especally in summer if you are silly as I to risk planting then and also especially to plants that came from a greenhouse or more "hospitable" climate.  It also holds very true to cactus, who have a keen sense of direction given that one side of the plant gets baked with Southern sun and the other may have never actually been kissed by the sun!

The "Stireman design" shadecloth tents, protecting summer-planted crevice-dwelling subjects.


A classic "moat" for Sporobolus airoides, Alkali sacaton. 

For shrubs and trees with larger, thirstier, root systems as well as any plant that is going to get watering (for establishment) infrequently.  The old-fashioned castle-moat -stlye water "well" is great.  The more water it can hold to soak in and charge the soil, the better.  I make tiny temporary dams in the crevice garden for small plants, too.


(note the small well at the top of this crevice-planted Arenaria hookeri spp. desertorum. 


Water Regime
Mirabilis alipes/multiflora? has no trouble its first season at all.

My jury is still out on this, but I think we're closer after this year.  I'll use the term "establishment-watering" to describe what is done with the purpose of getting a plant established, not what they will see in the future, because some will be intentionally unwatered for the rest of their lives while I fuss over different things.

I have been establishment-watering exactly once a week this year.  Honestly: Mondays.  I am starting to think that doubling up in would have cut the losses down.  Generalisations are dangerous, but I love danger:  I currently opine that more water when young gets the plants further along so as to have better plants who re ready when it is time to cut them off.  Another dangerous generalisation is to expect to establish-water for two seasons running before you can walk away entirely in the dry Western US.  This may mean much less frequently that second year.

A bigger specimen, (Like a five-gallon tree) and especially one with a pot-bound or in-grown root system will need to be watered over a longer span of time, as it will take it longer to establish than a small plant with loose roots, I find.  Bigger plants are thirstier, and  where root system shapes are concerned, old habits die hard for mature plants.

There is definitely no definite formula to water regime; the best method is to use one's judgement based upon trying the soil with one's finger.  And each plant is different- drastically so; and this is what keeps us interested.

Confession Time
I've lost 14% of all plants I stuck in the ground this year. (Out of well over 200 planted) Cold hard numbers rudely proclaim that there was much experimenting.  Murdering plants in the name of knowledge.  Checking my records closely, the majority of the doomed were planted in July, and died within a week or two.  Lesson: avoid July, and probably August, unless you like to water frequently. And even then, feel the shame.

Near Onion Creek Rd, Highway 128, Utah, USA

3 comments:

Lucie K said...

When I learned this technique from you in a class at T-line Gardens last spring, I immediately went home and dug up plants deposited the previous year. Wouldn't you know it, their roots were still suffocating in giant thimbles of potting mix. Thank you for sharing your wisdom so freely! All surviving plants in my garden are better for it! You rock!
Bob's guidelines for planting can also be found at: http://paridevita.com/2012/04/28/planting-in-a-dry-garden/


ineedacupoftea said...

Thanks for posting that link- I had seen that; let us hope the more we all talk about this technique, the more folks will adopt it; the results I have had personally are (and I can think of no other word) staggering. I just love (yes, this is a bit odd) to watch my new plants wilt a day or two before I water them- maybe out of satisfaction, either from watching them behave like established plants or knowing that had I planted them in the standard plug-in-light-socket style, they would not wilt temporarily but would do their best farewell-tour burnt-toast impression.

Haworthia said...

Good stuff Kenton. Definitely makes sense. We will have to swap books when I get back in a couple of weeks. Leo Chance's book "Cacti and Succulents for Cold Climates" is certainly worth a look and has some plants in there I would have never imagined could have been hardy anywhere in Colorado...I am now going to be buying up every Echinofossulocactus Home Depot carries just to see. P.S. I got you a Epithelantha micromeris from Leo for you to try.