Listed below are flower, vegetable and herb varieties that are great to start planting in October based on the Hardiness Zone that you live in.

Flowers (Zones 5-10):
October is a great time to plant those fall flowers. There are many varieties that can be planted this fall and start blooming early spring.
Suggested varieties: Celosia, Asters, Dianthus

Garlic (Zones 5-10):
Garlic is a vegetable that can be planted in the fall for a larger and earlier harvest this coming spring.
Learn More: How to Grow Garlic
Suggested varieties: Elephant, Spanish Roja, Inchelium Red

Herbs (Zones 3-10):
Herbs are definitely the most popular indoor plants to grow throughout the winter months. Try your hand with an indoor herb garden. Also check out the Urban Farmer Herb Kits.
Learn More: How to Grow Herbs
Suggested varieties: Aroma 2 Basil, Standard Chive, Greek Oregano, Giant of Italy Parsley, French Thyme