Answer: The answer to your question would depend on which plants you are considering. Many annuals can be started by direct seeding in the ground, and in fact many annuals do not transplant all that well and do better started in place. Some plants do not ship all that well and so would not be offered as plants. Some annuals grow so fast that it would not be cost effective to buy transplants. Most perennials can also be started by direct seeding, but it is more reliable to start them under the more controlled conditions indoors. Finally, some gardeners prefer to start certain varieties from seed because they are difficult (or nearly impossible) to locate as started plants. i hope this helps explain some of your question.
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