How to Start Herb Plants

Overview

There are a number of ways to start herb plants for the garden. Home gardeners or commercial growers can start plants from seeds or from cuttings or they can buy transplants for use in the garden. While many herbs can be started from seeds, there are certain herbs that are very slow growing such as rosemary or lavender, are difficult to germinate or do not grow "true" when started from seeds, as is common with mint. Starting herb plants from seeds is one of the least expensive options for gardeners and provides additional benefits to growers: It gives them a much greater selection of varieties and it allows the grower to set the timing specific to his planting schedule.

Plan Ahead

Step 1

Make a list of the herbs that you want to grow. Culinary herbs that you can grow from seed include basil, chives, coriander, dill, marjoram, oregano, parsley and thyme.

Step 2

Check local garden centers and gardening catalogs to find the varieties that you need. Most garden centers have a more limited selection of herb seeds than catalogs and they only stock seeds at certain times of the year. Seed houses offer a much greater assortment of varieties and they are typically available sooner.

Step 3

Buy your seeds or place catalog orders as far ahead as possible to avoid the possibility of a specific variety being sold-out or back-ordered. It is best to store seeds in a cool, dry place until you are ready to use them.

Set Up a Planting Calendar

Step 1

Determine which seeds will be direct-seeded outdoors and which will be started indoors. Starting plants indoors gives gardeners a head start as the seeds can be started at an earlier date. Herbs that you can sow directly in the garden include chervil, chives, cilantro, dill, parsley and sorrel.

Step 2

Determine the target date that you will transplant the seedlings into the garden. For spring gardens, this can be as early as your last frost date; it will be later for cold-sensitive herbs such as basil. Recommended nighttime temperatures for common culinary herbs are 45 degrees Fahrenheit for chervil, chives and sorrel; 50 degrees Fahrenheit for catnip, coriander, dill, fennel, lemon balm, oregano, parsley and thyme; 55 degrees Fahrenheit for anise hyssop, borage, feverfew, marjoram, sage and savory; and 65 degrees Fahrenheit for basil.

Step 3

Determine the time that it takes each of your herb varieties to germinate and grow to transplant size. Estimated times from seed starting to transplant size for common herbs are 36 days for basil, 31 days for chives, 29 days for coriander, 32 days for dill, 31 days for marjoram, 48 days for oregano, 34 days for parsley and 45 days for thyme.

Prepare Planting Containers

Step 1

Start herbs in cell trays, 4-inch pots or nursery flats. Fill the trays with a sterile growing mix. Purchase potting mixes ready to use from garden centers or gardeners can mix their own. A commonly recommended mix is the Cornell Peat Lite Mix made with peat moss and vermiculite or perlite along with starter nutrients. You can add compost or composted manure or vermicompost to the potting mix at a rate of 25 percent.

Step 2

Thoroughly saturate the planting medium. Immerse trays or pots into a larger container of water, allowing the water to be absorbed from the bottom.

Step 3

Scatter seeds over the top of the containers. Plant most herbs in bunches of four to six seeds per cell or per 4-inch pot.

Step 4

Cover the seeds with a light layer of potting mix and mist the top of the trays or pots lightly.

Step 5

Cover the trays or pots with damp newspaper or plastic and place them out of direct sunlight.

Germination

Step 1

Check your seeds frequently for watering and germination. Some seeds will germinate as soon as 3 days after seeding, others can take as long as 9 or 10 days. You can water by misting or from the bottom. Remove excess water from trays under the plants.

Step 2

Remove newspaper or plastic covers as soon as 50 percent of the seeds have germinated.

Step 3

Place the trays into indirect light until the first set of leaves (cotyledons) appears. When the first set of leaves appears, move them into full light, either sunlight or artificial light. Most light stands use adjustable fluorescent lights that should be set 4 to 6 inches above the trays.

Step 4

Add a half-strength water-soluble fertilizer to the irrigation water if you did not use compost or manure in the potting mix.

Transplant Seedlings

Step 1

When the first set of leaves emerges, transplant the seedlings from the cell trays to 2-inch or 4-inch pots. Take care to keep the soil level at the same depth as in the original containers.

Step 2

Water the transplants thoroughly and shade them from strong light for a couple of days to avoid shock.

Step 3

Increase the spacing between containers as the plants grow and the leaves of adjacent containers touch.

Step 4

When the plants are 2 to 4 inches tall and outdoor temperatures permit, transplant the seedlings into prepared containers or outdoor growing beds, following the spacing recommendations on the seed package.

Things You'll Need

  • Containers (cell trays, 2-inch or 4-inch pots or nursery flats)
  • Potting soil
  • Water
  • Herb seeds
  • Newspaper or plastic
  • Mister
  • Light stand (if starting seeds indoors)
  • Water-soluble fertilizer or compost

References

  • "Growing Herbs From Seed, Cutting and Root: An Adventure in Small Miracles;" Thomas deBaggio; 1994
Keywords: herbs, propagation, gardening, germination