Arizona residents who live in the desert valleys with its surrounding mountains (sometimes called “sky islands”) are a fortunate bunch. Biodiversity of plants and animals throughout our state is among the best anywhere on earth. We have a seemingly endless supply of flora and fauna to photograph, sketch, collect, and admire and for the most part we are hindered in our interactions only by our imaginations. However, for those of us who try and incorporate our favorite local plant into our home landscape, we are limited by the specific requirements that each plant must have to thrive and grow.

Seed pellets encapsulate seeds in a mixture (often clay, and nutrient-rich organic matter such as compost, humus, or charcoal) that will potentially reduce predation by insects and rodents while allowing for increased water retention and seed-soil contact. Seed pellets are an ancient method of sowing seed, and are especially useful in areas with compacted or dry soils. Seed pellets are strewn in the desired location (no need for soil preparation) and remain inactive until heavy rains arrive, washing away the clay and allowing seeds to germinate. Making seed pellets by hand is extremely time consuming and labor intensive. To make large numbers of seed pellets in a reasonable amount of time, we constructed a bicycle-powered seed pelletizing machine that effectively coats seed in clay and compost materials. It is designed to be easily taken apart for storage or transport,so each component fits against the others without being screwed together. The bicycle spins a barrel containing the seeds and coating materials while the operators periodically mist the contents with water. The result is coated seed balls that can be used for restoration or home gardening. Here, we explain how to construct the seed pelletizing machine.

Integrated Pest Management (IPM) is an ecosystem-based strategy that focuses on long-term management of pests or their damage through a combination of techniques such as biological controls, habitat manipulation, modification of cultural practices, use of resistant varieties, and chemical (UCIPM definition). Chemical controls are employed after other management techniques have proven ineffective and/ or significant crop damage continues to occur.

This publication explains how climate zones can assist in selecting appropriate plant material for different locations in Arizona. Climate zone maps include the USDA Hardiness Zone Map, the American Horticulture Society Heat Zone Map, and the Sunset climate zones. Arizona cities and commonly used landscape plants are listed with their classification according to the three climate zone maps.

Adeniums are popular as ornamental container plants. They combine a succulent growth habit and a wide selection of colorful flower forms. The name “desert rose” is often applied to adeniums. The name of the genus Adenium can double as a common name which avoids confusion with true roses grown in desert gardens.

The saguaro cactus (Carnegiea gigantea) is an iconic symbol of Arizona and the greater American Southwest. The saguaro flower is Arizona’s State Flower. Silhouettes of saguaro appear on the standard Arizona automobile license plate. Saguaro cacti are the largest cacti in the United States, sometimes exceeding 60 feet in height and standing taller than any other plant in their native habitat. Arizona’s two largest metropolitan areas, Phoenix and Tucson, feature saguaro cacti in urban natural areas and planted landscapes.

Grapefruit (Citrus × aurantium L. var. racemosa (Risso) ined.) formerly (Citrus x paradisi) is a fruit that can cause great disagreements. Many people believe that the fruit is excessively bitter, thick-peeled and/or difficult to eat, while many others enjoy the bracing flavor of the fruit, either fresh or juiced, as an essential part of a winter morning’s breakfast. Pummelos (Citrus maxima (Burm.) Merr.) are relatively unknown in the United States but are widely available in East Asian countries. Pummelos are slowly increasing in popularity due to returning travelers, East Asian immigrants and adventurous “foodies” who are willing to give them a try.

Rainwater harvesting is a sustainable way to augment or offset water for landscape irrigation and mitigate stormwater impacts in Arizona and the desert southwest. Annual evaporation in Arizona’s low deserts is 70 to 80 inches, and precipitation ranges from 4 to 12 inches per year (AZMET), which creates the need for supplemental water to insure healthy plant growth for non-native plants and for native plants in challenging settings such as hardscape-intensive urban areas. Longer, hotter summers, increasingly unreliable patterns of rainfall (National Oceanic and Atmospheric Administration (NOAA) 2017), and increasing population (US Census Bureau, 2018) will require more water conservation measures to ensure sustainable growth and development of urban trees and forests. Water harvesting is an important water conservation method that can supplement other water sources, and is increasingly seen as a discrete supply of water.

Desert gardening presents a host of challenges including: poor soils, high temperatures, intense sun, low humidity, and frequent winds. All of these factors are compounded by an arid to semi-arid climate with little rainfall, which makes proper irrigation a vital component for any successful gardening endeavor. Drip irrigation is widely accepted as the one of the most efficient systems to irrigate in desert gardens and landscapes because it minimizes water loss from evaporation or run off by delivering measured amounts of water directly to the soil (Schuch, 2016). However, drip irrigation may be ill suited for remote areas with low technology and/or unpressurized and unfiltered water systems. Drip systems can be costly, damaged, and emitters can be easily blocked with sediment, salt, and several insects (Ezekiel et al., 2017). Unreliable or impractical water sources for irrigation may discourage those wanting to develop a garden. For these situations, utilizing the ancient method of olla irrigation may be an option.

Annual bluegrass (Poa annua) is a cosmopolitan weed in most turfgrasses. In Arizona, the vast majority of the annual bluegrass is a true winter annual weed (Poa annua var. annua L. Timm.) that germinates in the fall, grows throughout the winter season, flowers profusely in the spring, and then dies as the summer temperatures rise. The weed seed remains in the soil all summer and then germinates during the next fall. The annual form var. annua is more upright in growth habit and prolifically produces stemmy seedheads that often grow in a circular pattern around the leaves, especially when the turf is mowed regularly.