With Don Shor & Lois Richter Gardening West of the Causeway

Davis climate and region River floodplain ‘Mediterranean’ climate: rainy winter, dry summer. Mix of soil types, mostly mineral Annual grasses and oaks ” of annual rainfall 90 degree highs June - September Delta breeze, coastal influence Several frosts between Nov. - February.

Hot summers Average high July - August: 90 degrees Many pleasant spells in the 80’s days over degree temperature swings Hottest ever: 117F. Hottest spells usually early - mid July Very low humidity from May - October Delta breeze is our natural air conditioner! Sunset Zone 14, USDA Zone 9.

Cold, wet winters First frost Thanksgiving, last frost Valentine’s Some nights in mid-20’s Lowest ever: 16F (1990 freeze) Latest frost ever: early April Significant freezes in 1990, 1998 Coldest spells usually mid - late December Tule fogs November - January Valley fog in December - early January

Storms & winter rain Typical storms form in Gulf of Alaska, move in through the delta south of us. ‘Pineapple express’ storms come across the warmer Pacific. Warmer, wetter. Typical first rain around Hallowe’en 1/2” - 1” typical per cold front Heaviest rainfall Dec. - February Significant rainfall rare after mid-May Flooding can occur after soil is saturated.

Wind! Prevailing winds from southwest are off the ocean, through the delta: help to moderate temperatures in the summer (‘delta breeze’) Gusty winds from the north are off the land: dry and hot in summer, dry and cold in winter. Desiccate plants, break tree limbs.

Soils Clay to sandy loams are typical. Sandier loams close to creeks. Denser clay loams on north, west. No true ‘hardpan’, but a ‘plowpan’ in some areas. Very low natural organic content. Water penetrates slowly, runs off readily. Soil naturally retains moisture: water slowly, deeply, infrequently.

Water Groundwater: water comes from wells. High in dissolved salts: calcium, boron, and others. High pH: water is alkaline. Acid-loving plants have special needs. Other plants may show nutrient deficiencies: iron, zinc.

What can we grow? summer and winter vegetables, herbs ‘stone’ fruit trees: apricots, cherries, peaches and nectarines, plums persimmons, pomegranates, figs nut trees cane berries citrus many subtropicals perennial flowers seasonal (annual) flowers

What plants have special needs? ‘Acid-loving’ plants require pH correction. some plants are easy to overwater in heavy soil areas. many apple varieties perform better with cooler autumns (and codling moth is a nuisance). some subtropicals are marginal; truly tropical plants must be inside Nov. - March. some high elevation or coastal plants can’t tolerate the long, hot, dry summer.