Rains in October have caused a βmassive germinationβ of annual wildflowers, which bodes well for a good bloom in the spring, according to wildflower experts.
βBut itβs been dry since mid-October, so the seedlings are probably not growing vigorously now,β said Mark Dimmitt, a retired director of natural history at the Arizona-Sonora Desert Museum and an authority on blooming patterns.
βWe need more rain soonβ to produce a standout bloom of annual wildflowers such as gold poppies and lupines.
Dimmitt said the October rains have already produced some floral beauty near his home.
βMexican gold poppies germinated in my yard with my 3ΒΎ inches (of rain) in October,β he said.
βI have watered them a couple of times since, and there are already a few flowers.β
Areas southwest of Tucson are offering more hope for a good bloom, Dimmitt said.
βI heard from a group who went to the Pinacate (a region in Mexico not far south of the Arizona border) two weeks ago that the area is lush,β he said. βOrgan Pipe Cactus National Monument (in Arizona south of Ajo) is probably the same.β
WHATβS NEEDED NOW
A critical first step β a so-called βtriggering rainβ of at least one inch β must take place in the autumn. That happened in October.
But more rain is needed for a spectacular bloom, as Dimmitt noted while he was at the Desert Museum in a paper called βPredicting Desert Wildflower Blooms β The Science behind the Spectacle.β
βThe triggering rain must be followed by regular rains totaling at least an inch per month through March, a season total of at least five inches, seven or eight are better,β he wrote.
βIn short, a really good wildflower bloom requires both an unusually early and an unusually wet winter rainy season.β
Those, Dimmitt noted, are the rain requirements for a very good bloom of annual wildflowers such as gold poppies, lupines and owl clover.
βPerennials are less fussy about the timing of rainfall,β he said.
βThus a late but wet rainy season can still produce good blooms of penstemon, larkspur (also sometimes known as delphinium), brittlebushβ and other perennial wildflowers.