Seed Markers are small wooden pegs that gardeners use to mark their plantings. Generally they are plain wooden or plastic sticks but you can buy more upmarket versions such as the ones below. If you think the cost of buying a pack of markers is not worth it, I believe you could find other uses for the remaining markers in your home or on other gifts.
If giving a gardening gift, you could use a seed marker as the gift tag. The ones below have holes at the top that you can thread a ribbon or twine through but you can always plant these in your gift (if its a plant) or glue to your gift bag/box.
A cute idea that fits with the theme!