We have a short growing season in Denver (zone 5b/6a), which means that some plants need to be started indoors and transplanted so they reach maturity in time to bear fruit. Seed packets typically contain growing information such as when to plant, depth, growing and transplanting requirements, and days to maturity. There are plants that gardeners typically direct sow (plant directly in the ground) that we start indoors; this is based on our understanding of the microclimates in our growing space and what has worked best for the highest yields. We encourage you to ignore the ‘shoulds’ and experiment to learn what works best for you! The list below is based on our experience gardening in this region.

Direct Sow - vegetables and herbs

• Carrots

• Parsnips

• Turnips

• Daikon

• Peas

• Beans / Fava Beans / Garbanzos / Cowpeas

• Corn

• Radishes

• Spinach

• Beets (can be started indoors for an early crop or direct sown for succession planting)

• Summer Squash*

• Winter Squash / pumpkins*

• Cucumbers*

• Melons*

• Lettuce*

• Gourds*

  *While these are typically direct sown, we start them indoors in compostable pots (especially melons as we have such a short season for those). When we plant out the seedlings, we’ll direct sow a few seeds around each transplant to ensure the plants make it. This method can be particularly useful there is an overpopulation of pill bugs that snack on newly sprouted seedlings. As many of these plants do not like root disturbance, planting them in compostable pots is helpful.

Start Indoors - vegetables and herbs

• Tomatoes

• Peppers

• Eggplant

• Onions

• Shallots

• Cabbage / Tatsoi

• Kale

• Collard and Mustard Greens

• Broccoli

• Cauliflower

• Kohlrabi

• Celtuce

• Chard*

• Tomatillos

• Ground Cherries

• Bok Choy / Pak Choi / Choy Sum / Yu Choy / Komatsuna / Mizuna

• Artichokes

• Sorrel*

• Celery

• Luffa

• Okra

• Celeriac

• Rosemary

• Parsley*

• Chives*

• Shiso / Perilla*

• Marjoram

• Sage

• Lavender

• Basil

• Bee Balm

• Amaranth

* Can also be direct sown, especially if succession planting.

Direct Sow - Flowers

• Achillea/Yarrow

• Poppies

• Sunflowers

• Nigella

Start Indoors - Flowers

• Asters

• Zinnias

• Stock

• Snapdragons

• Columbines

• Marigolds

• Strawflowers

• Statice

• Daises*

• Echinacea*

• Cosmos*

• Milkweed*

• Nasturtiums*

• Agastache*

• Strawflower

  *these can also be direct sown.

Others - Tubers, bulbs, rhizomes etc.

Some things either do best or are only available as bulbs, tubers, rhizomes, bulbs, or corms. Some examples are below.

• Garlic - seed garlic (garlic cloves) are planted in the fall for a summer harvest.

• Potatoes - certified seed potatoes can be purchased or organic grocery store potatoes can be used.

• Sweet Potatoes - slips (vine roots) are purchased and typically started indoors in our region.

• Shallots / Onions - sets (bulbs) can be purchased in lieu of starting these from seed.

• Hops - rhizomes can be started indoors or directly planted into the garden (be forewarned, hops will quickly overwhelm any garden bed it’s planted in).

• Tulips, Daffodils, Iris, Crocus, Lillies, Hyacinth, and Alliums are typically grown from bulbs planted directly in the garden.

• Dahlias - grown from tubers that are typically started indoors in our zone.

• Ranunculus - corms are typically started indoors and transplanted in our zone.