Total Soil Needed
23.0 gal
1 cu ft Bags
4
Total Plants
5
Select your plants to get recommended pot sizes and total soil.
Buy 1 extra bag to account for 10–15% soil settling after first watering.
| Plant | Qty | Pot Size | Soil |
|---|---|---|---|
| Peppers | 2 | 12" (5 gal) | 10.0 gal |
| Tomato (Determinate) | 1 | 14" (7 gal) | 7.0 gal |
| Herbs (basil, cilantro) | 2 | 10" (3 gal) | 6.0 gal |
| Pot Size | Summer | Spring / Fall | Self-Watering |
|---|---|---|---|
| 1–3 gal | Daily | Every 2 days | Every 4–5 days |
| 5–7 gal | Every 1–2 days | Every 2–3 days | Every 5–6 days |
| 10–15 gal | Every 2–3 days | Every 3–4 days | Every 5–7 days |
Stick your finger 1" into soil. Water when dry at that depth.
| Diameter | Volume | Best For |
|---|---|---|
| 6" | 0.5 gal | Single herb or microgreens |
| 8" | 1 gal | Herbs, lettuce, strawberries |
| 10" | 3 gal | Herbs, beans, strawberries |
| 12" | 5 gal | Peppers, eggplant, bush tomatoes |
| 14" | 7 gal | Cucumbers, bush tomatoes |
| 16" | 10 gal | Indeterminate tomatoes, squash |
| 18" | 15 gal | Large tomatoes, squash, zucchini |
| 24" | 25 gal | Multi-plant combos, small trees |
Inputs
Result
Three herb pots need about 5 gallons total. Three 8-quart bags (6 gal total) provides enough soil with a small reserve for settling.
Inputs
Result
Two indeterminate tomatoes need 12–15 gal pots each (24–30 gal), plus three peppers at 4 gal each (12 gal). Three 2-cubic-foot bags (45 gal) covers it with extra for settling.
Inputs
Result
A 12-inch pot holds about 5 gallons. Four pots need 20 gallons total. Three 1-cubic-foot bags (22.5 gal) fills them all with a bit left over.
Determinate (bush) tomatoes need a 5–10 gallon pot, while indeterminate (vining) tomatoes need 10–15 gallons. A standard 5-gallon bucket works for compact varieties, but larger pots produce better yields and need less frequent watering.
| Tomato Type | Min Pot Size | Ideal Pot Size | Pot Diameter |
|---|---|---|---|
| Cherry (determinate) | 5 gal | 7 gal | 14" |
| Bush (determinate) | 5 gal | 10 gal | 16" |
| Vining (indeterminate) | 10 gal | 15 gal | 18" |
Soil volume depends on pot size: a 5-gallon pot needs 5 gallons of soil (about 0.67 cubic feet), and a standard 2 cubic foot bag fills about 15 gallons. Buy 10–15% extra because soil settles after the first watering.
| Bag Size | Volume (gal) | Fills How Many 5-gal Pots |
|---|---|---|
| 8 qt bag | 2 gal | 0.4 pots |
| 16 qt bag | 4 gal | 0.8 pots |
| 1 cu ft bag | 7.5 gal | 1.5 pots |
| 2 cu ft bag | 15 gal | 3 pots |
Yes, many vegetables thrive in 5-gallon buckets including peppers, eggplant, bush beans, and determinate tomatoes. Drill 4–6 drainage holes in the bottom. Lettuce, herbs, and strawberries grow well in even smaller containers at 1–3 gallons.
Watering frequency depends on pot size, plant type, and weather. Small pots under 3 gallons typically need daily watering in summer. Large pots of 10+ gallons may only need watering every 2–3 days. Self-watering containers extend intervals to 4–7 days.
| Pot Size | Summer Frequency | Spring/Fall | Self-Watering |
|---|---|---|---|
| 1–3 gal | Daily | Every 2 days | Every 4–5 days |
| 5–7 gal | Every 1–2 days | Every 2–3 days | Every 5–6 days |
| 10–15 gal | Every 2–3 days | Every 3–4 days | Every 5–7 days |
The cheapest method is bulk potting mix delivered by the cubic yard, which costs $30–60 per cubic yard (about $4–8 per 7.5 gallons). Bagged soil costs $8–15 for 2 cubic feet. For very large pots, fill the bottom third with filler like pine bark or packing peanuts to reduce soil volume.
The best container vegetables are peppers, lettuce, herbs, bush beans, cherry tomatoes, and strawberries. These produce well in 1–10 gallon pots. Avoid plants with large root systems like corn and full-size watermelons unless you have 15+ gallon containers.
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Last Updated: Mar 9, 2026
This calculator is provided for informational and educational purposes only. Results are estimates and should not be considered professional financial, medical, legal, or other advice. Always consult a qualified professional before making important decisions. UseCalcPro is not responsible for any actions taken based on calculator results.