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Herbs, Flowers & Specialty CropsIndoor Herb Calendar
Indoor herbs fail more often from too little light than from anything else. A good indoor calendar tracks day length and your windows, not just the date on the wall.
Key points
- Indoor timing is set by light, not frost dates.
- Use supplemental light when winter windows are weak.
- Water by feel and use containers with drainage.
- Harvest lightly and treat pests only with label-approved methods for edible plants.
When should you start herbs indoors?
Unlike outdoor crops, indoor herbs are not tied to your last frost date. You can start them nearly any time. The practical limit is light. Extension sources from Penn State, Iowa State and Illinois note that winter days in many areas are short and weak for herbs, so starting in fall or winter works best if you plan for added light.
If you intend to move indoor-started herbs outside later, count back from your average last spring frost using the guidance on the seed packet.
How much light do indoor herbs need?
Most culinary herbs want a lot of light. A south-facing window helps in many areas, but winter sun can still be too weak. Iowa State Extension discusses supplemental lighting for herbs, and Penn State describes the light needs of common species. Fluorescent or LED grow lights placed close to the plants and run for a steady number of hours each day often improve results.
Watch the plants. Long, thin, pale stems and wide gaps between leaves point to low light. Move plants closer to the light or lengthen the daily period according to extension guidance.
Rotate pots a quarter turn every week so plants grow evenly instead of leaning toward the light. If you use grow lights, a simple outlet timer keeps the daily period steady, which plants prefer.
What containers, soil and watering work?
Use containers with drainage holes and a fresh, lightweight potting mix intended for containers. Garden soil is usually too heavy and may carry pests. Check moisture by touch and water when the surface layer has dried slightly, since soggy mix causes root rot, especially for woody herbs such as rosemary and thyme.
Most herbs prefer moderate, not hot, rooms, and cold drafts from windows at night can damage tender leaves.
Fertilize lightly and only according to the label of the product you choose, since indoor herbs grow slowly and excess fertilizer can burn roots or reduce flavor. Pots need to be flushed with water now and then if white crust builds on the surface.
Which herbs do well indoors?
Compact, leafy herbs tend to be easiest. Chives, parsley, mint, basil, oregano and thyme are commonly listed in extension guides, with differing light needs. Basil is more demanding about warmth and light; mint tolerates lower light but spreads in its pot.
Grouping herbs by water and light needs makes care simpler. Put drought-tolerant Mediterranean types together and moisture-loving types together.
- Easier: chives, parsley, mint, oregano, thyme.
- Harder: basil and other warmth-loving herbs, which need strong light and warmth.
- Plan to replace short-lived herbs on a rotation instead of expecting one pot to last all winter.
How do you harvest without wearing plants out?
Harvest lightly and often from the growing tips, taking only a portion of the plant at a time. Cutting just above a leaf pair encourages branching. If a plant stalls, rest it for a couple of weeks. Indoor plants grow slowly in low light, so harvest less than you would outdoors.
If you want to preserve extra herbs, use tested methods from the National Center for Home Food Preservation or your extension office.
What pests and problems appear indoors?
Common indoor problems include fungus gnats from overly wet mix, aphids and spider mites. Prevention starts with clean pots, moderate watering and inspection of new plants. If you must treat a pest, choose only products labeled for edible herbs and follow the label exactly, including intervals before harvest. Your extension office can help identify the problem and suggest options.
Quarantine new plants for a couple of weeks away from your other herbs, so any hitchhiking pests are caught before they spread.
How do you plan the year of indoor herbs?
Divide the year into three blocks. In fall, set up lights and start or pot up herbs. In winter, harvest lightly and watch light and water. In late winter and spring, either keep going under lights or prepare to move plants outdoors after frost danger. Record dates when you sowed, first harvest and when growth slowed so next year's plan reflects your own windows.
Expect some losses and replace plants as needed rather than treating each one as permanent. Starting a new pot every month or two keeps fresh growth coming, and it lets you try other herbs to learn which ones suit your windows, your lights and your cooking.
Sources and further reading
Last reviewed: November 2026. Educational information, ranges only. Confirm timing with your county extension office.