Last weekend (4-13-08), the poppies in the California Poppy Reserve State Park (http://www.parks.ca.gov/?page_id=627) east of Lancaster were near their peak, and were looking better than they had in several years.
There are also other flowers blooming, like lupines, cream cups, and goldfields, but these can be obscured by the profusion of poppies.
Lots of people are here on weekends, and next weekend is The Lancaster Poppy Festival (just west of Highway 14… not at the Poppy Reserve), so it could be even more crowded (http://www.poppyfestival.com/).
Luckily there are signs to educate the masses: people can learn where poppies go to battle their opium addiction, and also where the view is just so ugly that the embarrassed staff has to apologize for it.
Finally, if you can’t go on a weekday, and you want to avoid the crowds, you can find poppies outside the park, like this place north of the Reserve on Avenue D. This may be private property, but there are no fences or signs.