Answer: You've probably purchased the common lilac, Syringa vulgaris. Those with different color blooms are species lilacs and include Chinese Lilac (Syringa chinensis), Japanese lilac (Syringa japonica), or one of the French hybrids. These are generally available in local nurseries, or you can contact the Huntington Botanical Gardens, 1151 Oxford Rd., San Marino, 92208 ((818) 405-2141) to ask about their species sale. Just for future reference, you're in USDA zone 8.
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