Rinse the petals gently in a colander to remove dirt and tiny visitors. Drain well and pluck any remaining green bits.

Place the petals in a medium saucepan with 3 cups of water. Bring gently to a simmer, then lower heat and steep for 15 minutes.

Strain the petal infusion through a fine sieve or cheesecloth into a measuring cup, pressing lightly to extract all the liquid.

Return the dandelion liquid to a clean saucepan and stir in lemon juice and pectin.

Bring the mixture to a rolling boil over medium-high heat.

Add the sugar all at once, stirring until dissolved. Return to a vigorous boil and boil for 1 minute.

Remove from heat and skim off any foam for clarity.

Ladle the hot jelly into sterilized jars, leaving 1/4 inch headspace.

Clean rims, apply lids, and process in a boiling water bath for 10 minutes.

Let jars rest undisturbed for 24 hours. Store sealed jars in a cool, dark pantry for up to 1 year.