How to Grow Basil Indoors in an Apartment: A Complete Beginner's Guide

October 25, 2026

Basil grows fast, smells wonderful and goes into more recipes than almost any other herb. It is also the herb most likely to stretch, droop or turn bitter on an apartment windowsill. The good news is that basil fails for a short list of predictable reasons, and each one can be fixed.

This guide walks through every decision in order: the variety, the pot, the soil, the light, watering, pruning, harvesting and what to do when something goes wrong.

Choosing the right basil for indoors

Any basil can grow inside, but compact types fit small pots and windowsills better than tall Italian types. The University of Illinois Extension lists several compact or bushy cultivars, including:

Spicy Globe and Green Globe: small, dense, rounded plants that suit a windowsill
Emily: a compact Genovese type with the classic pesto flavor
Medinette: a compact sweet basil with large leaves

If you mainly want basil for pesto and cooking, a compact Genovese type is a good first choice. Standard Genovese works too; it just grows taller and needs more frequent pinching.

Seeds or a grocery store plant?

Seeds are cheap and reliable when kept warm. Illinois Extension notes that basil seed germinates best when the growing medium is at least 70°F and that harvesting can start in about four to five weeks. A potted basil from the grocery store gets you there faster, but it is usually several seedlings crammed into one pot. Gently split the clump into two or three groups and repot each so the stems are not competing for light and water.

Pot and drainage requirements

Use a pot at least 6 inches wide. Illinois Extension recommends pots of 6 inches or bigger for herbs and warns against growing basil in a small 3 inch pot, because it quickly outgrows it.

The pot must have a drainage hole. Water that cannot escape collects at the bottom and rots the roots. Set the pot on a saucer and empty the saucer after watering. A decorative pot without a hole can still be used as an outer cover, with the basil in a plain draining pot inside it.

Soil recommendations

Use a bagged potting mix made for containers, never garden soil. Garden soil packs down in pots and drains poorly. University of Maryland Extension suggests that for indoor herbs, a blend of two parts soilless potting mix to one part perlite improves drainage. A standard bagged potting mix on its own also works for basil.

Light requirements

Light is the biggest limit indoors. Iowa State University Extension notes that most herbs grown indoors need around eight hours of direct light a day, with some tolerating as little as six. Basil sits at the demanding end of that range.

Best: a south facing window with direct sun for most of the day
Workable: a bright east or west window, often with help from a grow light
Not enough on its own: a north facing window or a spot several feet back from the glass

If your basil gets less than about six hours of direct sun, add a grow light. Iowa State suggests keeping lights within 6 to 12 inches of the leaves on a timer set for 12 to 16 hours a day. Read How Much Light Do Indoor Herbs Actually Need? for a full setup.

Keep it warm

Basil is sensitive to cold. Pull pots back from cold glass on winter nights and keep them away from drafty doors and air conditioning vents.

Watering

Penn State Extension advises never letting basil potting mix dry out completely. At the same time, soggy mix rots roots. The simple routine:

Push a finger about an inch into the mix.
If it feels dry, water slowly until water runs from the drainage hole.
Empty the saucer after a few minutes.
If it still feels moist, wait and check again the next day.

How often that happens depends on your light, temperature, pot size and season, which is why a fixed calendar does not work.

Pruning for a bushy plant

Pinching is the habit that turns one stem into a full plant. Illinois Extension recommends pinching stem tips to encourage branching and removing flower buds as soon as they appear.

Wait until the plant has several pairs of true leaves.
Cut or pinch the stem just above a pair of leaves. Two new stems grow from that point.
Repeat on each new stem once it has a few more leaf pairs.
Pinch off flower buds as soon as you see them. Once basil flowers, leaf growth slows.

Harvesting

Harvest little and often. Take leaves from the top of each stem, cutting above a leaf pair, rather than stripping leaves from the bottom. Michigan State University Extension advises not clipping more than a third of an indoor herb at one time. A steady light harvest keeps the plant producing; one large harvest sets it back for weeks.

For a continuous supply, Illinois Extension suggests sowing new seed every two weeks so a younger plant is always coming along.

Common problems and solutions

Tall, thin, floppy stems

Almost always too little light. Move the pot to your brightest window or add a grow light, then pinch the stems back so new growth comes in sturdier.

Drooping leaves

Check the soil first. Dry mix means it needs water. Wet mix means the roots may be sitting in water; empty the saucer and let the top inch dry before watering again.

Yellowing lower leaves

Often overwatering or poor drainage. Iowa State Extension lists yellowing leaves, leaf drop and wilting as signs of roots sitting too long in wet soil.

Dark or blackened leaf edges

Usually cold damage. Move the plant away from cold glass and drafts.

Small or bitter leaves

Look for flower buds and pinch them off. Keep harvesting regularly.

Tiny flies around the pot

Fungus gnats breed in constantly wet mix. Let the top of the mix dry between waterings.

What to expect

Indoor basil usually will not match a summer garden plant in size, and Iowa State Extension notes that herbs grown indoors are often milder in flavor. With enough light and regular pinching, one or two pots can still supply fresh leaves for everyday cooking. Results always depend on your light, temperature, the variety you choose and your care, so treat the first few weeks as a test of your space.

If you would rather skip soil entirely, the Countertop Herb System walks through a simple jar based setup for basil and other kitchen herbs. For other herbs that cope better with lower light, see 7 Indoor Gardening Mistakes Beginners Make.

Start with your light

The most common reason basil fails indoors is a spot that looked bright but was not. The free 7 Day Indoor Garden Starter walks you through finding your real light before you buy a plant.

Sources

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