Successful Gardening

  at Double Diamond
 
 


Fact Sheet  - IF9

 
 

 1100 W. Moana Ln., Reno, NV 89509         11301 So. Virginia St., Reno, NV  89511
 

Key Points:

·        Boron vs. soluble salts and sodium

·        Soil conditioning

·        Raised beds

·        Water management

·        Plant selection

 

Boron vs. Soluble Salts and Sodium

 

Some of the most difficult growing conditions imaginable are found in the Double Diamond area. These conditions exist along the east side of the Truckee Meadows south of the Double Diamond area and extend north through the Spanish Springs area.  The causes of these adverse conditions include restricted drainage and often a high water table carrying dissolved salts and boron.

Soil tests indicate toxic levels of soluble salts and boron exist throughout the area.  However, the REAL problem is the presence of sodium which compounds existing drainage problems.  Boron and salts can be leached out IF drainage can be improved.  Soils are very fine, similar to talcum powder, thus water moves very slowly through these soils, if at all. Water ponding and runoff occur in a very short time, often as soon as five minutes after irrigation has begun.

 

Soil Conditioning

 

            The first step in soil condition is a soil test to determine levels of boron, soluble salts and sodium.  The next step lies in soil conditioning to improve the drainage and maybe even installing drainage pipes.  The new homeowner needs to increase drainage as deep as possible and replace the sodium that is tied to the soil.  The other soluble salts and boron can be leached downward.  This may not be as easy as it sounds as drainage is restricted for several feet down and is also affected by a high water table.  As this water table rises during a wet spring, salts, including sodium, are re-deposited at the surface when the water table recedes. During wet springs the salts will rise through any new topsoil that has been used, contaminating it as well.

Depending upon the soil test and sodium results, the reclamation may be started by the addition of 50 to 100 pounds of gypsum per 1000 sq. feet.  The gypsum should be worked into the soil as deeply as possible, 6”-8” minimum.  This will help release the sodium from the soil particles so they can be leached downward. Gypsum needs to be added to the lawn area especially, as once the lawn is in you will not be able to effectively condition the soil again.  Ideally, gypsum should be added and tilled in BEFORE adding any topsoil.  Add half of the topsoil needed, 1 ½”- 2” of organic matter and rototill again.  Some artificial drainage using perforated pipe at this time is strongly recommended.  Establish the rough grade and add the final half of the topsoil. Do not rototill this last time. This blending of gypsum, organic material and topsoil will help prevent the creation of any interfaces or abrupt texture changes and allow water to infiltrate into the lower profiles more easily and rapidly.  This will also encourage deeper turf rooting.  Use gypsum and organic material wherever you intend to plant, ideally over the entire yard or shrub/tree bed.

 

 

            The next step is proper planting.  This is a very critical factor.  Prepare the planting hole as wide a you have energy for but a minimum of 3 times the diameter of the root ball --5 times would be better (Fig. 1).  The root ball should be only deep enough to enable the root ball to sit on firm, undisturbed soil. 

 

Text Box:

This depth should place the root ball at the same depth as it was before or even up to one inch higher.  It is highly recommended that the outer, bottom edge of the hole be dug 6”-8” deeper and sloped upward toward the center plateau (Fig. 1).  Soil removed from the hole should be conditioned with equal parts of soil, organic matter and gypsum.  Use your shovel for a measuring tool.  Mix very thoroughly and backfill in the hole, and water when the hole is ¾ full.  Do not place rock or gravel in the bottom of the hole to “aid drainage.”   Water simply will perch or sit on the rock-soil interface.  For perennials, ground covers, flower beds and vegetable gardens, rototill 50-100 pounds of gypsum per 1000 sq. feet as well as 4”-6” of organic matter into the soil 6”-8” deep and over the entire area.  You may also consider using raised beds for some planting.

 

 

 

Raised Beds

 

You may consider raised beds for planting.  They allow plants to develop in good topsoil or triple mix soil above the native Double Diamond soil.  Beds may be constructed of wood, rock, brick or keystone blocks and should be minimum of 18” high.  Put a cap on top for extra seating.

 

Water Management

 

            Soil conditioning is the key for plant survival but proper watering is also vital.  Keep in mind at all times DRAINAGE IS RESTRICTED.  Water will move very slowly through the soil and watering too much, too fast, is a common cause of ponding, runoff, waterlogged soil and drowned plants.

In turf areas apply water slowly and for short periods of time, usually 5 minutes or less.  Stop watering and wait until all the stations on the controller have cycled for about 30 minutes minimum and rewater.  Do this several times on your watering days until moisture has reached 6”-8” deep.  Check your soils with a trowel or shovel before and after you water to see how deep the water has infiltrated and what is remaining from the previous irrigation.  It would probably be best to record the times for future controller settings.  Remember that most sprinklers and sprinkler systems apply water much faster than the soil can absorb it, especially spray nozzles.

Drip irrigation is recommended for several reasons but must be monitored as well to avoid salt accumulations around the high points of berms, etc.  A monthly overhead watering with a hose and sprinkler over the entire planting area is recommended to leach the accumulated salts down.

 

Plant Selection

 

            Plant selection is another key to the puzzle of successful gardening.  Plants that are salt tolerant and drought resistant should be used.  The plants on the following list are generally recommended for planting in Double Diamond area.  There may be some on the list that won’t grow in your specific microclimate and some, not listed, that will grow.  The list is intended as a guide only.  The trees only are listed in order of most tolerant to least.

 

 

I.                    Trees

·        Idaho Locust                                              Robinia ambigua ‘Idahoensis’

·        Flowering Crabapple                                  Malus species

·        Purple-leaf  Plum                                        Prunus cerasifera ‘Atropurpurea’

·        Thornless Honeylocust                                Gleditsia triacanthos 

·        Raywood Ash                                            Fraxinus angustifolia ‘Raywood’

·        Bradford Pear                                            Pyrus calleryana

·        Common Hackberry                                   Celtus occidentalis

·        Bur Oak                                                     Quercus macrocarpa                         

·        Goldenrain Tree                                          Koelreuteria paniculata

·        Amur Maple                                               Acer tataricum ‘Ginnala’

·        Trident Maple                                             Acer buergeranum

·        English Oak (pyramidal)                              Quercus robur fastigiata

·        Blue Ash                                                    Fraxinus quadrangulata

·        Norway Maple                                           Acer platanoides

·        Sycamore                                                   Platanus occidentalis                         

·        European Hornbeam                                   Carpinus betulus                                            

·        Hawthorne                                                 Crataegus species                              

 

II.                 Evergreen Trees

·        Rocky Mountain Juniper                             Juniperus scopulorum

·        Pinon Pine                                                  Pinus edulis

·        Austrian Pine                                              Pinus nigra

·        Scotch Pine                                                Pinus sylvestris

·        Arizona Cypress                                         Cupressus arizonica

·        Atlas Cedar                                                Cedrus atlantica

·        Incense Cedar                                            Calocedrus decurrens

·        Bristlecone Pine                                          Pinus aristata

 

The following shrubs and perennials need water in order to properly get established, followed by less irrigation as they mature.

 

III.               Shrubs

·        Peashrubs                                                  Caragana arborescens

·        Flowering Quince                                       Chaenomeles species

·        Butterfly Bush                                             Buddleia species

·        Smoke Tree                                               Cotinus coggygria

·        Cotoneasters (all)                                       Cotoneaster species

·        Scotch Broom (all)                         Cytisus scoparius

·        Silverberry                                     Elaeagnus commutata

·        Burning Bush                                              Euonymus alatus ‘Compacta’

·        Juniper (most varieties)                               Juniperus species

·        Beauty Bush                                               Kolkwitzia amabilis

·        Privet (all)                                                  Ligustrum species

·        Mock Orange                                            Philadelphus coronarius x virginalis

·        Mugo Pine                                                 Pinus mugo

·        Arborvitae                                                  Thuja species                          

·        Potentilla                                                    Potentilla fruticosa

·        Pyracantha                                                 Pyracantha coccinea

·        Sumac                                                        Rhus species

·        Arctic Willow                                             Salix purpurea

 

IV.              Perennials and Ground Covers

·         Apache Plume                                            Fallugia paradoxa

·        Yarrow                                                      Achillea millefolium

·        Basket of Gold                                           Aurinia saxatilis

·        Rock Cress                                                Arabis species

·        Sea Pink                                                    Armeria maritima

·        Snow-in-Summer                                       Cerastium tomentosum

·        Mock Strawberry                                       Fragaria species                                             

·        Lambs Ear                                                 Stachys byzantina

·        Mother of Thyme                                       Thymus serpyllum

·        Veronica                                                    Veronica species

·        Ajuga (some)                                             Ajuga species

·        Periwinkle                                                  Vinca species

·        Kinnickinick                                               Arctostaphylos uva-ursi

·        Horizontal Cotoneaster (all)                        Cotoneaster species

·        Genista                                                       Genista lydia

·        Halls Honeysuckle                          Lonicera halliana

·        Mahonia Creeping                          Mahonia repens                                             

·        Bishop’s Weed (dense shade)                    Aegopodium podagraria

·        Daylilies                                                     Hemerocallis species

·        Gaura                                                         Gaura lindheimeri

·        Ornamental grasses                                    Various species