Hello, fellow gardeners! I’ve been growing basil for more than 10 years, and I can tell you that the soil depth is very important for success. This afternoon, I’m going to talk about what I know about planting basil seeds at the right depth and how to grow great basil at home.
Quick Answer
Plant basil seeds 1/4 inch (6mm) deep in well-draining soil Though some gardeners go as shallow as 1/8 inch or as deep as 1/2 inch depending on soil type,
The Perfect Planting Depth for Different Situations
Indoor Starting
- Seed starting mix depth: 1/4 inch
- Container requirements: Use cells/pots with drainage holes
- Seeds per cell: 2-3 seeds
- Soil coverage: Light sprinkle of starting mix
Direct Outdoor Sowing
- Light soil: 1/2 inch deep
- Heavy clay soil: 1/8 inch deep
- Standard garden soil: 1/4 inch deep
- Row spacing: 12-15 inches apart
Step-by-Step Planting Guide
-
Prepare Your Container
- Fill with seed starting mix
- Leave 1cm space at top
- Pre-moisten soil thoroughly
-
Plant the Seeds
- Make shallow 1/4″ depression
- Drop 2-3 seeds per spot
- Cover lightly with soil
- Mist gently with water
-
Provide Optimal Conditions
- Temperature: 70-85°F (21-29°C)
- Light: Bright but indirect until sprouting
- Moisture: Keep consistently damp
- Ventilation: Good air circulation
Common Mistakes to Avoid
- ❌ Planting too deep
- ❌ Using dry soil
- ❌ Overcrowding seeds
- ❌ Poor drainage
- ❌ Inconsistent watering
Key Growing Requirements
Temperature
Ideal germination: 75-85°F (24-29°C)Minimum soil temp: 70°F (21°C)Maximum soil temp: 85°F (29°C)Timing
- Germination: 5-10 days
- First true leaves: 14-21 days
- Ready for transplant: 4-6 weeks
- First harvest: 6-8 weeks
Pro Tips from My Experience
-
Soil Moisture
I always pre-moisten my soil before planting. Dry soil can wash away tiny seeds when watering later.
-
Seed Spacing
Don’t be stingy with seeds! I plant extra knowing some won’t make it. You can always thin later.
-
Light Requirements
Once sprouted, basil needs 6+ hours of direct sun. I learned this the hard way with leggy seedlings!
-
Temperature Control
Keep it warm! To keep the right temperature, I put a heat mat under my seed trays.
Troubleshooting Common Issues
Seeds Not Germinating?
- Check soil temperature
- Ensure consistent moisture
- Verify seed freshness
- Confirm proper planting depth
Weak Seedlings?
- Increase light exposure
- Improve air circulation
- Reduce watering frequency
- Check for proper spacing
Care After Germination
-
Thinning
- Wait for true leaves
- Keep strongest seedlings
- Space 4-6″ apart
- Cut extras at soil level
-
Feeding
- Start after true leaves appear
- Use half-strength fertilizer
- Feed every 2 weeks
- Choose organic options
-
Hardening Off
- Start 7-10 days before transplant
- Gradually increase outdoor time
- Protect from strong winds
- Watch temperature carefully
My Favorite Basil Varieties
-
Sweet Basil
- Classic flavor
- Great for pesto
- Easy to grow
-
Thai Basil
- Spicy anise flavor
- Heat tolerant
- Beautiful purple stems
-
Genovese
- Large leaves
- Strong flavor
- Perfect for cooking
Final Thoughts
Remember, growing basil isn’t rocket science! The key is getting that planting depth right (1/4 inch is your sweet spot) and providing consistent warmth and moisture. I’ve killed plenty of basil plants learning these lessons, so don’t get discouraged if your first attempt isn’t perfect.
Got questions about growing basil? Drop ’em in the comments below! I love helping fellow gardeners succeed with their herbs. Happy planting!
Last updated: July 2025
DAY 115: HOW TO HARVEST AND PRESERVE BASIL
Youve done it! The beauty of Basil is that once it is established into the garden and the temperatures are consistently warm, it becomes a very low maintenance plant!.
All you need to do for the rest of the season is keep pruning the plant, and this will be your ongoing harvest. Rather than plucking individual leaves at any point, always prune the stems and take the leaves from that. This will ensure the plant doesnt go to flower and that new foliage growth is put on.
The plant will have small black spots when the weather starts to cool down at the end of the season. This means it is starting to have trouble. At this point, pull the plant entirely from the garden and harvest off all the leaves. This pile of leaves lets you make a lot of pesto at once, which you can then freeze in single servings to enjoy all winter long.
By following those steps at the key moments through the season you should be setup extremely well to have lush and bountiful basil!
Q: How to fertilize basil?
Start your basil seeds in a Worm Castings Seedling Mix to ensure it has nutrients and microbes from the beginning. At the point of transplanting, amend the soil with both Pure Worm Castings and 4-4-4 Superfood to give it all the nutrients and microbes it needs to thrive as the warmer days of summer approach.
Start Basil from Seeds & Stop Buying Expensive Transplants: How to Grow Beautiful Basil Plants!
FAQ
How deep do you plant basil seeds?
Whether I’m using small pots or cell trays, I plant my basil seeds about 1/4 inch deep and about an inch apart. It’s essential not to bury them too deeply because they need light for optimal germination. A cozy temperature between 75°F and 85°F is critical for good germination rates.
How do you plant basil seeds?
Follow these simple steps for proper basil seed planting Fill starter pots or trays with seed starting mix. Moisten the soil before planting. Sow seeds 1⁄4 inch deep, spacing 1-2 inches apart. Gently water the soil after planting to further settle seeds. Cover pots or trays with plastic wrap or dome lids to retain moisture.
How many basil seeds should I plant?
When sowing basil seeds in cell packs, plant 2 to 3 seeds per cell. If starting basil seeds in 4 inch pots, plant 6 to 8 seeds per pot. Whatever type of container you are using for the basil seeds, sow each seed about an inch apart. Plant the seeds a quarter of an inch deep. The exception to this is holy basil whose seeds need light to germinate.
How far apart should Basil seedlings be planted?
Let my basil seedlings have more space when they get their second set of true leaves, which look like real basil leaves. I transplant them into my garden, spacing them about 10 to 12 inches apart. This gives each plant enough space to spread out and breathe, which is crucial for healthy growth.
How deep do you plant holy basil?
Note: Holy Basil requires some light for germination, so sow more shallowly than other basils. Transplant: Sow indoors 6 weeks prior to setting out. Plant 1/4″ deep and keep at 70°F (21°C) for best germination. How do you plant holy basil? Note: Holy Basil requires some light for germination, so sow more shallowly than other basils.
How long does it take for basil seeds to grow?
Basil seeds germinate best when soil temperatures are 75-85°F and take about 10-14 days to sprout. Plant transplants after the last frost in mid to late May. They need four to six weeks to grow to their full size. So the soil doesn’t dry out, plant the seeds 1/8 inch deep and cover them with soil just a bit.