Heat broth in saucepan. Keep warm on low heat.
Heat olive oil in large heavy-bottomed pan over medium heat.
Add onion. Cook 4 to 5 minutes until soft.
Add garlic. Cook 30 seconds.
Add arborio rice. Stir to coat. Toast 2 minutes.
Add lemon juice. Stir until absorbed.
Add one ladle warm broth. Stir frequently until absorbed.
Continue adding broth one ladle at a time. Stir after each addition. This takes 20 to 25 minutes.
After 15 minutes, add asparagus. Continue adding broth.
When rice is almost tender, add peas. Add one more ladle broth.
Cook 3 to 4 more minutes until peas are tender and rice is creamy.
Remove from heat. Stir in Parmesan, butter, and lemon zest.
Season with salt and pepper.
Serve immediately. Garnish with herbs, Parmesan, and lemon wedges.