|How many weeks before that last frost date should I plant the following seeds indoors under grow lights. They will be transplated outdoors later. Impatiens, Marigolds, Nasturtiums, Poppies, Oriental poppies, Violas and Zinnias.
|Traditionally your last frost date is about mid-May. All of the seedlings you mention can go outdoors 6-8 weeks after your last frost date, so plant them indoors now, or wait until the end of May and sow them directly in your prepared garden beds.