Care Of Cacti In Containers


Cacti are a group of succulent plants that do well in containers under the right conditions. They are native to the New World. These plants are diverse both in form and color, clumping or solitary. They can range in size from very small to more than 40 feet tall. Most cacti are best grown outdoors in filtered sun or on a bright patio. Some can tolerate full sun. Smaller species may be kept in a container. The larger varieties can start out containerized but will outgrow their pots and can be moved to the landscape, depending on the species, where they can enjoy more growing space.

SOIL: Most cacti should be grown in mineral-based soils consisting of a mixture of sands, silts, and gravel (good drainage) and which does not harden when dry. Cacti from tropical dry forests and high altitude regions benefit from a mix containing 25-50% decomposed organic matter. Epiphytic cacti such as Christmas cacti like a 1/3 – 1/3 – 1/3 mix of bark, pumice and decomposed organic matter. No peat should be used in any of these mixes. Organic matter consisting of well-decomposed plant material or worm castings is acceptable. If you wish to use peat-based soil mixes, you can, provided that you re-pot every 2-3 years. No commercial mixes come up to these standards as of this time, so you will need to formulate your own.

WATER: It is completely false that cacti need no water; after all, they are composed principally of water. What is true is that they require less water than violets, but more than a rock. Water cacti when they are actively growing or are wilting. Wilting appears as shrinkage of the plant or wrinkling of the surface. Most cacti grow actively in the spring and summer, but some grow in the other seasons as well so you will need to watch them carefully. Water only when the soil is nearly dry. You can test for dry sub-surface soil with your finger, a wooden pencil or popsicle stick (damp soil will cling to the wood), or (best) with a moisture meter. Water all of the soil thoroughly until the water runs out of the drain holes. Use only pots with drain holes, and if you use pots with saucers, be sure to empty the saucer after watering. The rule is ―no swamps.‖ The warmer the weather, the more frequently water is needed, unless the plant is dormant. In winter, little or no water is needed, even for cacti in active growth, because it is cool. Natural rain is very beneficial, and water may be applied from overhead (which helps clean the plant), at the soil line, or from below. Remember not to let the plant stand in a saucer of water.

LIGHT: Cacti, excepting epiphytes, are best grown outdoors. Interiors are usually too dark for good growth unless assisted by high-intensity lights. Cacti grown indoors very frequently develop pointy heads or other forms of stem stretching. Cacti should be grown outdoors in conditions ranging from full sun to 50% shade, depending on the species and on the size of the plant. If the cactus gets too much sun it will sunburn, which results in a yellowing of the skin, progressing to a browning (killing) of the skin on the sunniest side. If this occurs, provide shade immediately. Eastern exposures are gentlest, western sunlight is fiercest.

FERTILIZATION: Container grown plants need fertilizer because the soil will be exhausted of nutrients over time. The frequency of fertilization depends on how fast you want the plant to grow and the strength, or  concentration, of the fertilizer that you use. Remember that fast growth may produce weak cells, leading to over-tenderness. Fertilize at least once every four weeks during the plant’s growing season. Use the concentration recommended for ornamental plants on the fertilizer package. If you fertilize with each watering cut the strength of the solution accordingly. Use a low nitrogen fertilizer, such as 10-30-20. As a slow-acting organic fertilizer, fish emulsion is effective.

TRANSPLANTING/REPOTTING: Transplanting should be done when the plant has filled the pot, or, in the case of tall species, when the pot becomes top-heavy. If the soil in the new destination is the same or similar to that in which the plant is growing, simply shake the plant free of its container, keeping the soil ball intact if possible. Rough up the edges of the soil ball and then replant, keeping the soil level the same as the former location. If the soil/root ball collapses, wait a week to let the roots callus, then plant, using dry soil. If you are changing soil types from organic to mineral, first remove all old soil from the roots using an old toothbrush to get at the most stubborn bits. Cut off any broken roots and let dry until all wounds have callused over, then re-pot or plant using dry soil to fill in so that the soil will flow and fill in all air pockets. Wait a few days, then water in to settle the soil. It is best to transplant when the plant is actively growing, but if you must, you can do it anytime.

PESTS AND DISEASES: Cacti have few diseases and pests. Most problems are environmental. Pointy heads in globular cacti or stringy narrow stems in others–Etiolation caused by too little light–give more light. Yellowing or browning of the skin: especially on the sunny side—Sunburn—give more shade immediately. Wilting, wrinkling, shrinkage: dry soil, needs water. If the soil is wet, then roots have died due to swamping—remove from damp soil, re-root, and transplant. White cottony masses or white rice-like objects on plants: Cochineal scale or mealy bug—wash off with a hard jet of water, or apply alcohol or a pesticide for scale insects. Inspect plant often to check for recurrence. Very fine spider webbing in the spines: sometimes with red bead-size mites, and graying of the skin—Red spider mite. Wash off the water and use overhead watering to prevent reoccurrence. In severe cases use miticide treatment. Large larvae (grubs) tunneling inside stems, large black adults feeding on tips of plant: Longhorn beetle—remove adults at dawn and kill, or place them in a large prickly pear cactus clump some distance away.

Plant being eaten: Rabbit, rodent or javelina damage—Protect plant with a wire cage or move out of reach. Wet rot anywhere on the stem: Bacterial rot (Erwinia carnegieana)—Cut away all rotted tissue down to fresh, discolored tissue. Air dry. Do not fill in holes. Dry rot on tips or in the whole plant: Fungal dry rot (Helminthosporum cactivorum)—Cut away all dried and discolored tissue. Air dry.

Desert Composting

Composting is the managed decomposition of organic matter through biological processes resulting in humus material that can be used to improve soil structure. As a soil amendment, compost loosens heavy clay soils and enhances aeration. It allows sandy soils to hold moisture and nutrients for root absorption. Many home gardeners create compost piles in their backyards. Cities and towns encourage this to alleviate the unnecessary quantities of organic material going to landfills. Process: A compost pile is essentially an active microbial community. In the process of decaying organic matter, bacteria are the initial, most numerous and effective decomposers. Fungi and protozoa also break down plant tissue and somewhat later in the cycle centipedes, millipedes, beetles, earthworms and other organisms do their part. As microorganisms work to digest the material in a compost pile, they produce heat and carbon dioxide. This is why an active compost system will heat up. The result of this high temperature is that very few, if any, pathogens and weed seeds survive the aerobic composting process. 

Composting structures: The type of structure or method chosen to make compost is really a matter of personal preference. Materials can be composted in a heap or a bin can be used to contain materials neatly. If the compost system is going to be visible it should be tidy and somewhat attractive. Some people don’t mind seeing a pile of leaves in the back yard but a well built composting unit or a manufactured recycled plastic bin may be more desirable where aesthetics are a consideration. There are three basic types of composting structures: holding units, multi-stage units, and enclosed bins. Holding bins are the simplest type and are constructed of recycled wood, block, hardware cloth or any material that will hold the organic matter together. Multi-stage units are a series of two or more bins. They are appropriate for homes, community areas, or institutions with large gardens and high volumes of organic waste. 

Material in one bin can decompose while new materials can be placed into a second bin. A third bin can be used for final curing. Enclosed bins are the most appropriate for small yards. Construct an enclosed bin at home using a barrel or garbage can. A variety of bins including models that rotate or roll is available through garden centers and mail order catalogs. Many cities offer compost bins to homeowners at little or no cost. Any structure used should be at least three feet tall and wide to hold an adequate amount of material. 

Materials: All organic materials contain carbon and nitrogen in varying proportions. In general, moist green materials such as plant trimmings, fresh grass clippings, and kitchen vegetable scraps contain a higher proportion of nitrogen while dry brown materials such as dead leaves, brush, straw, and paper contain a higher proportion of carbon. To create ideal conditions for decomposition mix materials in the compost pile so that there is an approximate ratio of 3:1 brown carbon to green nitrogen. A pile with more brown material will still decompose but it will take longer. If too much green material is added the pile may develop an odor. 

Do not add any meat, dairy products, fats, oils or pet feces as these may cause odors or contain pathogens. Surface Area: The more surface area the microorganisms have to work on the faster the materials are decomposed. Chopping garden wastes or running them through a shredding machine or lawnmower will speed the composting process. 

Moisture and Aeration: The microorganisms in compost need oxygen and moisture to survive. They function best when the compost materials are kept about as moist as a wrung-out sponge. It is easy to moisten the pile as it is built and when turned. Turning or mixing the pile every one to two weeks provides the necessary oxygen for the microorganisms and significantly expedites the composting process. A pile that is not turned may take three to four times longer to decompose. Time: The composting process can take approximately two months to a year. The following practices will speed the decomposition of materials: – Keeping the proper proportion of carbon and nitrogen materials in the pile; – Turning the pile and keeping it moist; – Cutting large items into smaller pieces before adding them to the pile. 

Using Compost: Mix compost into vegetable and flower beds, blend it with potting soil to revitalize container plants, or spread it on lawns as a fertilizer. Use compost as a mulch around less desert-adapted trees and shrubs to cool the root zone and increase soil moisture retention during summer months. Most desert natives do not need compost as a soil amendment since they have evolved to thrive in soils with low organic content.

Problem Guide For Southwest Gardens

A noticeable, fine web may be present on your Palo Verde trees (Parkinsonia spp.) and even from time to time on the Whitethorn Acacia (Vachellia constricta syn. Acacia constricta).  This “webbing” is produced by the Palo Verde webworms often called Palo Verde webbers. The webworm is a small caterpillar that feeds on the leaves and occasionally the bark of the small stems.  The Palo Verde tree and Whitethorn Acacia are resilient to webworm infestations so control methods are unnecessary. The caterpillars and adult moths are an important food source for many lizards and birds.
If you notice a tattered appearance on your landscape plants such as Evening Primroses (Oenothera spp.), Sacred Datura (Datura wrightii) and Gaura (Gaura lindheimeri) it may be the flea beetle in action. A different species of flea beetle may also harm your vegetables including tomatoes and eggplants. The flea beetle larvae and adults can be destructive and they can be difficult to control. To find out more information on flea beetles go to the following link: http://ag.arizona.edu/maricopa/garden/html/t-tips/bugs/flea-btl.htm
Agave snout weevils become active during the warm months and infestation may not be apparent until it is too late. For detailed information on the life cycle, symptoms,
While sitting underneath your desert trees, you may notice a light “rain” falling. This is the smoke tree sharpshooter insect expelling sap as it draws from a variety of plants including Palo Verdes (Parkinsonia spp.), Beebrush (Aloysia gratissima), Bird of Paradise species (Caesalpinia spp.) and Hackberries (Celtis spp.). These sharpshooter insects have gone virtually unnoticed until they threatened oleanders, shrubs widely used in low-desert landscapes for screening hedges. They gained notoriety because they are able to transmit a deadly bacterial disease called oleander leaf scorch. Our native plants do not appear to be adversely affected by the smoke tree sharpshooter so no control is necessary.  To find out more about oleander leaf scorch check out the University of Arizona Extension Plant Pathology athttp://cals.arizona.edu/PLP/plpext/diseases/trees/oleander/oleleaf.htm
As the weather warms, whiteflies may be present on your landscape, vegetable and herb plants. These tiny, white insects have sucking mouthparts that cause leaves to yellow, wilt and drop prematurely. The immature nymph stage does more harm to the plant than the adult. Whiteflies can be difficult to control. Allow natural predators such as spiders, ladybugs, lacewings and even hummingbirds to control the population. Yellow sticky traps can also be used to control the adult population.
Noticeable leaf damage may be seen on the Texas Mountain-laurel (Calia secundiflora syn. Sophora secundiflora) during the warm months. The damage is caused by the sophora pyralid caterpillars feeding on the tender new growth. These ravenous caterpillars are approximately an inch long with orange bodies and interesting black spots with white hairs.
Psyllids can still be active during the month of May, but activity will decrease as the temperatures climb.  Psyllids are sap feeders and many are plant specific or feed on a closely related group of plants. High populations of psyllids can cause distortion and die back of new growth, and in some cases defoliation. To keep populations under control do not overwater or over fertilize your plants as this causes excessive growth. Yellow sticky traps can also be used to control the adult population.
Cochineal scale, the cottony, white substance on your Prickly-pears (Opuntia spp.) and Chollas (Cylindropunita spp.) may be active now. Remove by using a fast stream of water or spray insecticidal soap.
Fine webbing between leaves or stippling on leaves may indicate the presence of spider mites. These plant mites cause damage by sucking contents from the leaves and are difficult to detect due to their small size. Plants that are water stressed may become susceptible to infestation. Dusty conditions can also lead to spider mite outbreaks. Make sure your plants are well-watered and wash off accumulated dust on plants to manage spider mite problems. You can also remove by using a fast spray of water or by spraying insecticidal soap to control populations. There are many biological controls that feed on spider mites including lacewings, predatory mites, lady bugs and big-eyed bugs. Using insecticides is not recommended as insecticides do not help manage the population, but can actually cause the population to intensify because insecticides used will often kill their natural enemies. Some insecticides can even accelerate mite reproduction.
If you notice a rank odor and black ooze dripping down the saguaro stem(s), the plant may have developed an infection as a result of an injury or frost damage. The infection is caused by the Erwinia bacteria, a common bacterium found in the environment.
For more information on diseases or problems of landscape plants go to the University of Arizona Cooperative Extension publication/sites/dbg.dd/files/pldiseases_urban-1124.pdf or the University of California UC IPM Online athttp://www.ipm.ucdavis.edu/PMG/menu.homegarden.html.

Fertilizing A Southwest Garden

Most native and desert-adapted plants in the landscape do not generally require fertilizer as they are adapted to our soil conditions. In most cases, fertilizers are generally applied to prevent deficiencies. If fertilizers are needed, one application for the year is usually sufficient. If you did not fertilize in March or in April, go ahead and fertilize your landscape plants if necessary.  However, it is recommended to fertilize your landscape plants the early part of May. For more information on fertilizing and plant deficiencies go to the University of Arizona Cooperative Extension Publications: http://ag.arizona.edu/pubs/garden/az1020.pdf and /sites/dbg.dd/files/nutrient_deficiencies.az1106.pdf0_s.pdf
Periodically fertilizing may be needed for plants in containers as nutrients in the soil will have diminished over time. Always follow directions on the label.
Continue to fertilize your warm-season annuals and herbaceous and woody perennials in containers if necessary. 
Cacti and warm-season succulents in containers should be fertilized at least once during the month. Do not fertilize any winter-growing succulents such as Live Forever (Dudleya saxosa ssp. collomiae), Succulent Geraniums (Pelargonium spp.), Iceplants (Malephora spp.,Drosanthemum spp., Cephalophyllum spp.), Living Stones (Lithops spp.) and crassulaceous plants (Kalanchoe spp., Cotyledon spp., Echeveriaspp.) as they are now undergoing their summer dormant period.
Continue to fertilize your vegetable and herb garden as needed.

Pruning Your Southwest Garden

Pruning should be done to maintain plant health (remove dead, damaged or diseased portions, cross branching, etc.), to highlight the “natural” shape of the plant, to train a young plant, and to eliminate hazards. Excessive or heavy pruning causes significant stress to trees and shrubs. The best practices are to prune the least amount necessary and prune for legitimate reasons. How much to prune depends on the size, species, age, as well as your intentions. Two good principles to remember–a tree or shrub can recover from several small pruning wounds faster than from a single large wound and never remove more than 25% of the canopy in a year. For more information register for a Garden class offered on pruning that will teach you the proper pruning techniques for trees and shrubs or visit http://www.treesaregood.org for information on proper pruning of young and mature trees.
If necessary, native and desert-adapted spring-flowering shrubs can be pruned after flowering has diminished. However, prune before the upcoming hot, summer months. For more information on pruning shrubs go to the University of Arizona Cooperative Extension at:http://cals.arizona.edu/pubs/garden/az1499.pdf
Lightly prune your Mesquites (Prosopis spp.) and Palo Verdes (Parkinsonia spp.) to remove dead and crossing branches.
Pruning newly planted trees and shrubs is not recommended and in fact, can be detrimental.  However, at planting time prune broken or torn and diseased branches. Save other pruning activities for the second or third year. For more information on developing a healthy tree visit http://www.treesaregood.org
Prune Prickly-pears (Opuntia spp.) or Chollas (Cylindropuntia) after flowering.   If pruning your prickly-pears or chollas to maintain size, for propagation or to remove a damaged or diseased stem, prune at the joint or segment.  Use a sharp, clean pruning tool and spray tool periodically with a 70% alcohol solution to prevent infection. If the pruned stem is to be used for propagation, allow the cutting to dry out for a week before planting.
Continue to remove spent stalks of aloes, agaves, and other succulents.
Spring-blooming perennials such as Penstemons (Penstemon spp.), Brittlebush (Encelia farinosa), Globemallow (Sphaeralcea ambigua), Fleabane (Erigeron divergens), and Golden Columbine (Aquilegia chrysantha) should be producing seed. Allow them to produce seed before pruning spent flowering stems. The seed is a valuable food source for many animals.
Deadhead herbaceous perennials to encourage continued flowering including Desert Marigold (Baileya multiradiata), Chocolate Flower (Berlandiera lyrata), Red Sage (Salvia coccinea), Mealy-cup Sage (Salvia farinacea), Gaura (Gaura lindheimeri), Tickseeds (Coreopsis spp.), Angelita-daisy (Tetraneuris acaulis), and Gaillardia (Gaillardia pulchella).

What To Plant In May

Planting can still be done during the month of May. However, it is crucial that newly planted plants are monitored carefully. Follow the watering schedule for newly planted plants in the watering section.
When planting native and desert-adapted plants, it is usually unnecessary to back-fill with soil amendments and vitamins or to add rooting hormones. However, a slow-release fertilizer high in nitrogen and phosphorous can be added to the backfill, if needed. 
Many cacti can be started from seed at this time.  Seed can be soaked overnight in water to help start the germination process. Place seed in a well-draining soil mix (½ quality potting soil and ½ perlite or pumice) and lightly cover with potting mix or gently press the seed into the soil. Keep soil moist until germination occurs.
SOW SEED OF WARM-SEASON HERBACEOUS PERENNIALS INCLUDING:
• Mexican Hat (Ratibida columnifera)
• Red Sage (Salvia coccinea)
• Desert Senna (Senna covesii)
• Sacred Datura (Datura wrightii)
• Mealy-cup Sage (Salvia farinacea)
VEGETABLES TO TRANSPLANT INCLUDE:
• Jerusalem artichoke
• sweet potato
• watermelon
• tomatillo
• jicama
• eggplant and pepper (by mid-month)
VEGETABLE SEEDS TO SOW INCLUDE: 
• Black-eyed peas (early part of May)
• cantaloupe
• okra
• tepary beans
• muskmelon
• tomatillo
• yardlong bean
• pumpkin
• summer and winter squash
• watermelon
Try the variety of melons from Native Seeds/SEARCH.
HERBS TO TRANSPLANT INCLUDE:
• basil
• Mexican-oregano (Lippia graveolens)
• Mexican-tarragon (Tagetes lucida)
• Cuban-oregano
HERBS SEEDS TO SOW INCLUDE:  
• amaranth
PLANT WARM-SEASON CACTI & SUCCULENTS INCLUDING: 
• Saguaro (Carnegiea gigantea)
• Prickly-pears (Opuntia spp.)
• Chollas (Cylindropuntia spp.)
• Barrel cacti (Ferocactus spp.)
• Hedgehogs (Echinocereus spp.)
• Pincushions (Mammillaria spp.)
• Easter Lilies (Echinopsis spp.),
• Paper-spine Cholla (Tephrocactus articulatus var. papyracanthus)
• Agaves (Agave spp.)
• Aloes (Aloe spp.)
• Candelilla (Euphorbia antisyphilitica)
• Desert Spoon (Dasylirion wheeleri)
• Giant Hesperaloe (Hesperaloe funifera)
• Slipper Plant (Pedilanthus macrocarpus)
• Elephant Food (Portulacaria afra)
• Burseras, Elephant Trees (Bursera spp.)
• Madagascar-palm (Pachypodium lamerei)
• Madagascar-ocotillo (Alluaudia procera)
• Dyckia spp.
• Carrion Flowers (Stapelia spp.)
• Texas-tuberose (Manfreda maculosa)
• Limberbushes (Jatropha spp.)
• Red-yucca (Hesperaloe parviflora)
Most Yuccas (Yucca spp.) can be planted with the exception of Joshua Trees (Yucca brevifolia).
When transplanting cacti and succulents, mark either the south or west side and plant facing the orientation you marked to avoid the burning of tender tissues. Most nurseries will mark the side of the container to help you determine proper planting orientation. However, if the original orientation is not known, newly planted cacti and succulents need to be covered with shade cloth if the plant surface appears to yellow or pale suddenly. Use a shade cloth rated between 30-60% as anything higher will block most of the sunlight and will not be suitable for your cacti and succulents. You may need to keep the shade cloth on the plant for the duration of the summer.
PLANT NATIVE AND DESERT-ADAPTED TREES INCLUDING: 
• Ironwood (Olneya tesota)
• Blue Palo Verde (Parkinsonia florida)
• Little-leaf Palo Verde (Parkinsonia microphylla)
• Mesquites (Prosopis spp.)
• Golden Leadball Tree (Leucaena retusa)
• Desert-willow (Chilopsis linearis)
• Palo Blanco (Mariosousa willardiana syn. Acacia willardiana)
• Catclaw Acacia (Senegalia greggii syn. Acacia greggii)
• Canyon Hackberry (Celtis laevigata var. reticulata syn. Celtis reticulata)
• Texas-ebony (Ebenopsis ebano)
• Twisted Acacia (Vachellia bravoensis syn. Acacia schaffneri)
• Feather Tree (Lysiloma watsonii)
• Anacacho Orchid-tree (Bauhinia lunarioides)
• Vitex (Vitex agnus-castus)
• Baby Bonnets (Coursetia glandulosa)
PLANT WARM-SEASON SHRUBS INCLUDING: 
• Yellow Bells (Tecoma spp.)
• Texas-sages (Leucophyllum spp.)
• Creosote (Larrea tridentata)
• Superstition Mallow (Abutilon palmeri)
• San Marcos Hibiscus (Gossypium harknessii)
• Desert Cotton (Gossypium thurberi)
• Guayacán (Guaiacum coulteri)
• Sennas (Senna spp.)
• Velvet-pod Mimosa (Mimosa dysocarpa)
• Ocotillo (Fouquieria splendens)
• Fire Bush (Hamelia patens)
• Ruellia (Ruellia peninsularis)
• Lantana (Lantana camara)
• Mexican Bush Sage (Salvia leucantha)
• Silver Nightshade (Solanum hindsianum)
• Little-leaf Cordia (Cordia parvifolia)
• Showy Mendora (Menodora longiflora)
• Sky Flower (Duranta erecta)
• Bird of Paradise species (Caesalpinia spp.)
PLANT WARM-SEASON HERBACEOUS PERENNIALS AND GROUNDCOVERS INCLUDING:
• Sacred Datura (Datura wrightii)
• Desert Four O’Clock (Mirabilis multiflora)
• Arizona Foldwing (Dicliptera resupinata)
• Buffalo Gourd (Cucurbita foetidissima)
• Mealy-cup Sage (Salvia farinacea)
• Yerba Mansa (Anemopsis californica)
• Rose-mallow (Hibiscus coulteri)
• Wine Cups (Callirhoe involucrata)
• Hummingbird Trumpet (Epilobium canum ssp. latifolium)
• Chocolate Flower (Berlandiera lyrata)
• Desert Senna (Senna covesii)
• Trailing Lantana (Lantana montevidensis)
• White Plumbago (Plumbago scandens)
• Mist Flower (Conoclinium dissectum)
• Rain-lilies (Zephyranthes spp.)
MANY VINES CAN ALSO BE PLANTED AT THIS TIME INCLUDING:
• Yuca (Merremia aurea)
• Queen’s Wreath (Antigonon leptopus)
• Yellow Orchid-vine (Callaeum macropterum)
• Passionflowers (Passiflora spp.)
• Arizona Canyon Grape (Vitis arizonica)
• Old Man’s Beard (Clematis drummondii)

Watering Your Southwest Garden In May

As the weather warms, plant water needs will increase. Now is the time to adjust your watering schedule for the summer. Observe plants regularly for signs of water stress. Some signs to look for include:  wilting, curling leaves, yellowing or falling of older leaves, and dead stems or branches.
The amount of water and watering frequency depends on many factors. These include soil type, weather (temperature, humidity, rainfall, etc.), microclimates, cultural practices, plant size and species, and whether newly planted or established in the landscape (two years or more). Below are general guidelines to help you determine how much and how often to water your landscape and container plantings to keep them healthy when rainfall is lacking.
Established native or desert-adapted trees and shrubs should be watered at least once to twice monthly. Water at least 3 feet deep for your trees and 2 feet deep for your shrubs. Always allow the soil to dry out between each irrigation cycle.
Natural rainfall may be adequate for most well-established cacti and succulents. However, if rainfall is insufficient, water may be needed at least once to twice during the month of May. Water your cacti and succulents to a depth of at least 8-12 inches. Always allow the soil to dry out between each irrigation cycle.
Established herbaceous perennials, groundcovers, and vines should be watered every two to three weeks and at least 1 foot deep. Always allow the soil to dry out between each irrigation cycle.
Wait a week after planting your cacti and succulents before watering to minimize the chance of rot. After the initial irrigation of your succulents, allow the soil to dry out and water every 10-14 days. Cacti need to be watered once more after initial watering during the month but allow the soil to dry out between watering.
Newly planted native and desert-adapted trees and shrubs may need to be watered more frequently until established. It can take up to 3-5 years for trees and at least 1-2 years for shrubs to become established in the landscape.  After planting your trees and shrubs, they should be watered immediately and the moisture monitored for the next few days to keep the root ball from drying out. Schedule your irrigation cycle for trees and shrubs every 7-10 days during the month. Allow the soil to dry out between irrigations and always water deeply, 3 feet for trees and 2 feet for shrubs.
Newly planted native and desert-adapted herbaceous perennials, groundcovers and vines should also be watered immediately and for the next few days to keep the root ball from drying out. Schedule your irrigation cycle for herbaceous perennials, groundcovers, and vines for at least once to twice weekly and to a depth of 1 foot. Allow soil to dry out between watering.
Agaves and other succulents (Aloe spp., Pachypodium lamereiBeaucarnea recurvataPedilanthus macrocarpusEuphorbia spp., Gasteria spp.,Haworthia spp.) in containers should be watered at least once to twice this month. Cacti in containers should be watered at least once this month. However, cacti and succulents in small containers may need to be watered more often especially cacti and succulent seedlings.
Keep an eye on your warm-season annuals and herbaceous perennials in containers. Water them at least once to three times weekly.
Herbs may need to be watered every 3-5 days and vegetables need to be watered every 2-3 days. Water your herb and vegetable plants to at least a foot in depth.