Last Updated on September 17, 2026
How Many Basil Plants per Square Foot?
1 basil plant per square foot, 12 inches apart, for full-size sweet basil like Genovese. That is the spacing the Plan My Garden planner and my raised bed layouts use, and it leaves room for a plant you keep picking: Penn State Extension lists basil at 12 to 24 inches wide. Dwarf basils can go up to 4 per square (6 inches apart), the top of the 2 to 4 range on my square foot gardening chart.
The spacing pattern
| Full-size basil (Genovese type) | Dwarf basil (Spicy Globe type) | |
|---|---|---|
| Per square foot | 1 | up to 4 |
| Inches apart | 12 inches | 6 inches |
| 4 x 4 bed (16 squares) | up to 16 | up to 64 |
| 4 x 8 bed (32 squares) | up to 32 | up to 128 |
| 3 x 6 bed (18 squares) | up to 18 | up to 72 |
Those bed numbers are grid maximums, not a planting target, and few kitchens want a whole bed of basil. Utah State University Extension suggests 5 to 10 plants per person for fresh use, plus another 5 to 10 for storage. My 4×4 bed layout gives basil one square and the 4×8 layout gives it three.
Why sources say 1, 2 or 4 basil plants per square foot
The numbers disagree because they come from different ways of growing basil. My chart gives the tighter square foot gardening figure, 2 per square for larger varieties and 4 for smaller ones, to fit more plants in limited space. The planner gives a full-size plant the whole square, which lines up with the 12 inches or more that extension guides use. Each source, converted to a square foot bed:
| Source | Spacing | Per square foot |
|---|---|---|
| Plan My Garden planner and my bed layouts | one square per plant | 1 |
| My square foot gardening chart | 2 for larger varieties, 4 for smaller ones | 2 to 4 |
| Utah State University Extension | final stand 12 inches apart | 1 |
| Penn State Extension | 12 to 18 inches apart | 1, down to 1 per 2.25 square feet |
| University of Illinois Extension | at least 2 feet apart | 1 per 4 squares |
| Johnny’s Selected Seeds | 4 to 8 inches apart in rows 18 inches apart | 1 to 2 |
The math: 18 inches each way is 2.25 square feet per plant, and a plant every 4 to 8 inches in rows 18 inches apart gets 72 to 144 square inches. Johnny’s writes for field rows and cuts the entire plant 4 to 6 inches above the ground for a second growth. For basil picked stem by stem until frost, the home garden guides above all say 12 inches or more.
Variety is the other reason. Penn State Extension groups ‘Genovese’, ‘Napoletano’, ‘Lettuce Leaf’ and ‘Mammoth’ with the large-leaf basils and ‘Spicy Globe’ and ‘Spicy Bush’ with the small-leaf or dwarf ones, and Johnny’s lists Spicy Bush at 8 to 14 inches tall. Those small types are the ones for 4 per square.
Spacing also matters for disease. Iowa State University Extension calls ‘Genovese’ one of the varieties most susceptible to basil downy mildew and says to avoid overcrowding, keep air moving, and avoid overhead watering and watering at night. Resistant varieties it lists include Prospera and Rutgers Obsession.
Planting the square
- Start seed indoors 4 to 5 weeks before your last frost, about 1/4 inch deep (West Virginia University Extension). Utah State says it germinates best in 75-85°F soil and sprouts in 10 to 14 days.
- Set plants out 3 weeks after your last frost, once nights stay above 60°F, the mark Penn State Extension uses.
- Put one full-size plant in the center of the square. For a dwarf type, set four plants, one in the center of each quarter.
- Start harvesting when the plant has 6 to 8 leaves, cutting the stem so 2 to 4 leaves remain (Utah State).
When to plant basil
These are the windows the Plan My Garden planner uses, counted from your average last spring frost. Turn the weeks into dates with the seed starting calendar, or enter your zip code on Plan My Garden.
| Start indoors | 4 to 5 weeks before your last frost |
|---|---|
| Transplant out | 3 weeks after your last frost |
| Direct sow | n/a |
| Days to maturity | about 60 days |
| Frost tolerance | Tender: basil is readily damaged by frost (Iowa State University Extension), which is why it goes outside after your last frost |
Growing notes
Keep picking so it does not flower: Illinois Extension says basil that flowers and sets seed turns woody, stops producing and tastes bitter. Its method: cut the whole stem just above a pair of leaves, and new growth appears at the cut within a week. Illinois Extension also notes that freshly cut basil keeps best in a vase of water at room temperature.
Holy basil (Ocimum tenuiflorum, Iowa State) is a different species. My post on growing holy basil for tulsi tea gives each plant about a square foot, since it spreads quickly, and pinches off the top leaves and buds so the lower nodes grow.
Where to get seed
Wood Prairie’s organic basil seed includes Genovese (listed at 68 days, with several cuttings of leaves off the same planting), Rosie (a red basil at 65 days with compact, upright plants) and Lemon Basil (more compact than the common European basils). Code PMG5 takes 5 percent off.
Quick questions
How many basil plants fit in a 4×8 raised bed?
Up to 32 full-size plants at one per square, or up to 128 dwarf plants at 4 per square. Most gardens need far fewer; my 4×8 layout gives basil 3 squares.
What is basil spacing in square foot gardening?
One full-size plant per square, 12 inches apart. Dwarf types such as Spicy Globe can go up to 4 per square, 6 inches apart.
Can you plant 4 basil plants in one square foot?
Only a small dwarf type. Penn State Extension lists basil at 12 to 24 inches wide, and Iowa State University Extension says to avoid overcrowding to lower the risk of downy mildew.
How many basil plants do I need?
Utah State University Extension suggests 5 to 10 plants per person for fresh use, plus another 5 to 10 for storage.
Let the planner place them
Plan My Garden is free to start: enter your zip code, draw your beds, pick basil and everything else you want to grow, and it places each plant at square-foot spacing and builds a planting schedule from your frost dates.
Related: Square Foot Gardening Chart · Seed Starting Calendar · 4×4 Raised Bed Garden Layout · How Many Pepper Plants per Square Foot?
