If you start seeds indoors, you have probably come across Bootstrap Farmer. They have become one of the most trusted names in seed starting gear — and for good reason. Heavy-duty plastics, consistent sizing, and a product line that actually makes sense together.
But their catalog has grown, and it is not always obvious which pot to grab for what. This guide breaks down every Bootstrap Farmer pot size, what each one is actually good for, and how to get the most out of them — including a trick for adding depth without transplanting.
Bootstrap Farmer Square Pot Sizes
Bootstrap Farmer makes three square pot sizes. Each fits into standard 1020 nursery trays with the right insert.
32-Cell Tray Inserts (2" Cells)
- Cell dimensions: 2" × 2" square, 2" deep
- Tray dimensions: 21¼" × 11¼" × 2" deep (full insert)
- Fits: 1020 tray (also doubles as a holder for 2.5" pots)
- Source: bootstrapfarmer.com product listing, verified Feb 13
Note: Bootstrap Farmer does not sell standalone 2" pots. The 2" size comes as cells in the 32-cell plug tray insert. These are true seed-starting inserts — perfect for germination and the first couple of weeks. Lettuce, herbs, and flowers do well here. Tomatoes and peppers will outgrow them fast, usually within 2–3 weeks of sprouting.
Best for: Germination, microgreens to transplant, herbs, lettuce starts.2.5" Square Pots (Seed Starting Pots)
- Dimensions: 2.5" × 2.5" square, 3" tall
- Drainage: ¼" drainage holes
- Material: Heavy-duty injection-molded PP (#5), BPA-free
- Colors: Black, plus multicolor options (green, blue, purple, orange, pink)
- Fits: 32 pots per 1020 tray (use 32-cell plug tray insert)
- Source: bootstrapfarmer.com product listing, verified Feb 13
A step up from the 2" inserts. The extra half inch makes a real difference for root development. These are the classic Bootstrap Farmer seed starting pots — the ones most growers start with.
Best for: Seedling starts that will be transplanted outdoors or up-potted. Peppers, tomatoes (short-term), herbs, flowers.3.3" Square Pots (Heavy Duty)
- Dimensions: 3.3" wide, 4.3" tall
- Drainage: 0.62" drainage hole on bottom
- Material: BPA-free food-safe PP (#5)
- Colors: Black, plus multicolor options
- Fits: 18 per 1020 tray (with 18-hole insert), 9 per half-tray insert
- Source: bootstrapfarmer.com product listing, verified Feb 13
This is the workhorse. The 3.3" pot is where serious seedling growing happens. At 4.3 inches tall, it holds significantly more soil than the 2" or 2.5" inserts, and the heavy-duty construction means you can reuse these for years.
For tomatoes and peppers, this is the pot you want if you are keeping seedlings indoors for more than a few weeks. The depth lets roots develop properly, and the 83mm width fits neatly into standard 1020 trays — 18 pots per full tray insert.
Best for: Tomatoes, peppers, eggplant, larger herb starts, any seedling you need to hold for 4–8 weeks before transplanting. Pro tip: If your seedlings are outgrowing even these and it is still too cold to transplant, PlantSphere makes 3D-printed extensions that snap onto the top of these exact pots. The Standard Extension adds 2 inches of depth, and the Tall Extension adds 4 inches — no transplanting, no root disturbance. More on that below.5" Square Pots (Up-Potting)
- Dimensions: 5⅛" × 5⅛" square, 6" tall
- Material: BPA-free food-safe PP (#5)
- Colors: Black, plus multicolor options
- Fits: 8 pots per 1020 deep tray (with insert)
- Note: Not compatible with humidity domes
- Source: bootstrapfarmer.com product listing, verified Feb 13
The 5" pot is for when seedlings have truly outgrown the 3.3" size and need a bigger container before going in the ground. These are commonly used for tomatoes, peppers, and other plants that need a longer indoor growing period.
Best for: Up-potting tomatoes and peppers that need more time indoors, container herbs, any plant that needs more root space before final transplant.Bootstrap Farmer Cell Trays
Beyond individual pots, Bootstrap Farmer sells plug-style cell trays in various configurations. All cell trays fit standard 1020 trays, and all outer tray dimensions (except the 32-cell) are 21¼" × 11¼" × 2¼".
| Cell Tray | Cell Size | Cells per Tray | Best For |
|---|---|---|---|
| 4-cell insert | 2⅜" top, tapers to 1¼" bottom (air prune) | 4 per insert, 8 inserts per 1020 | Up-potting, crops that need room |
| 6-cell insert | 1½" × 1½" × 2⅛" top, tapers to 1" (air prune) | 6 per insert, 12 inserts per 1020 | Bigger transplants, variety tracking |
| 32-cell | 2" × 2" × 2" deep | 32 | Home gardeners, rockwool starts |
| 50-cell | 1¾" × 1¾" | 50 | Balance of space and quantity |
| 72-cell | 1½" × 1½" × 2¼" deep | 72 | Most popular — market gardeners |
| 72-cell air prune | 1.37" top, tapers to 1" bottom, 2.29" tall | 72 | Longer growing without root circling |
| 128-cell | 1" × 1" × 2¼" deep | 128 | High-density row crops, baby greens |
| 200-cell | ¾" × ¾" × 2¼" deep | 200 | Maximum density — cole crops, lettuce |
Cell trays are great for starting large batches of the same crop. The trade-off is that individual cells are smaller than standalone pots, so plants need to be transplanted sooner.
Other Bootstrap Farmer Containers
4-Cell Air Prune Insert
- Insert dimensions: 5¼" × 5¼" × 4" tall
- Cell size: 2⅜" at top, tapers to 1¼" at bottom
- Air-prune slits: 2½" long, ⅛" wide
- Drainage: Extra-large ¾" hole per cell
- Material: FDA Prime Grade PP (#5), BPA-free, USA-made
- Fits: 8 inserts per 1020 tray, 4 per 1010 tray
- Soil capacity: 1 cup per cell, 1 quart per insert
- Note: Not compatible with humidity domes
- Source: bootstrapfarmer.com product page, verified Feb 15
An alternative to the 5" pot for up-potting. The air-pruning slits prevent root circling, producing a healthier root system. Good for tomatoes and peppers that need more space before transplanting.
5×5 Deep Tray
- Dimensions: 5⅛" top width, 4¼" bottom width, 2¼" tall
- Drainage: Six drainage slits
- Fits: 8 per 1020 tray
- Material: BPA-free food-grade polypropylene
- Note: Not a precise fit in 1010 trays
- Source: bootstrapfarmer.com product page, verified Feb 15
A compact tray designed for microgreens, wheatgrass, and small-batch herbs. Think of it as a mini flat rather than a deep pot — at 2¼" tall, it works well for shallow-rooted crops. Bootstrap Farmer also makes a shallower version (1.3" tall) for even more compact growing.
Square Black Plastic Pots (Gro Pro® Premium)
- Size 1: 6.4" × 6.4" × 8.1" tall
- Size 2: 9.9" × 9.9" × 10.2" tall
- Material: PP (#5) injection-molded plastic
- Features: Heavy-duty design, stand-off feet for drainage
- Also available in white (same dimensions, from $36.99)
- Source: bootstrapfarmer.com product page, verified Feb 15
These are much larger containers for mature plants, not seed starting. They do not fit neatly into 1020 trays (only 3–4 of the 6" size fit loosely for bottom watering).
Fabric Grow Bags
Bootstrap Farmer makes fabric grow bags in eight sizes, all from food-safe BPA-free polypropylene felt (350 g/m²) with reinforced handles:
| Size | Height | Diameter | Soil Volume | Best For |
|---|---|---|---|---|
| 2 gal | 7" | 8" | 0.30 cu ft | Single houseplant or annual |
| 5 gal | 12" | 10" | 0.66 cu ft | Single plant or small greens |
| 7 gal | 12" | 13" | 0.93 cu ft | Tomatoes, peppers, eggplant |
| 10 gal | 14" | 14.5" | 1.3 cu ft | Root crops, small fruit trees |
| 25 gal | 18.5" | 20" | 4.0 cu ft | Potatoes, mixed plantings |
| 50 gal | 19" | 28" | 6.68 cu ft | Perennials, small shrubs |
| 100 gal | — | — | 10.3 cu ft | Raised bed alternative |
| 200 gal | — | — | 26 cu ft | Raised bed alternative |
The 7-gallon size is also available in multiple colors (green, blue, purple, orange, pink). The breathable fabric encourages root pruning — roots grow to the edge and self-prune instead of circling, which leads to a stronger root system and less transplant shock.
The 1020 Tray System
Everything Bootstrap Farmer makes is designed around the standard 1020 nursery tray (10" × 20"). This is the foundation of their system:
- Standard 1020 tray — The base. Holds water, provides structure.
- 1020 deep tray — Taller walls for more water capacity and larger pots.
- Tray inserts — Grid inserts that hold individual pots in place. Critical for keeping pots from tipping, especially with taller or top-heavy plants.
Why Tray Inserts Matter
This is something a lot of new growers skip, and they regret it. Without an insert, your pots sit loose in the tray. They are fine while everything is small and light. But the moment you add soil depth — whether from a larger pot or an extension — the pots get top-heavy. Pick up the tray and half of them fall over.
Bootstrap Farmer 1020 tray inserts hold 18 of the 3.3" pots securely. If you are growing anything in the 3.3" pots, get the inserts. Your future self will thank you.
Choosing the Right Pot for Your Crop
Tomatoes
Tomatoes are the most common reason growers run into pot size problems. Here is the progression:
- Start seeds in 2" or 2.5" inserts, or 72-cell trays
- First transplant (2–3 weeks) into 3.3" pots
- If stuck indoors longer than expected, either up-pot to 5" or add a PlantSphere extension to the 3.3"
Tomatoes root along their buried stems, so depth is more valuable than width. The 3.3" pot at 4.3" deep is already solid — and with an extension adding another 2–4 inches, you can hold tomatoes indoors for 6–8 weeks without them becoming root-bound.
Peppers
Peppers grow more slowly than tomatoes and are less demanding on root space early on. The 3.3" pot is usually enough for the entire indoor growing period. If you started very early (January or February for a spring transplant), you might need the extra depth.
Herbs
Most herbs are happy in the 2.5" inserts for their entire indoor life. Basil is the exception — it grows fast and benefits from the 3.3" pot.
Lettuce and Greens
These have shallow root systems. The 2" or 2.5" inserts are perfect. You can even grow lettuce to maturity in a 2.5" pot if you are doing cut-and-come-again harvesting.
When Your Seedlings Outgrow Their Pots
This is the situation every indoor grower faces at least once: your seedlings are too big for their current pots, but it is too early — or too cold — to put them outside.
The traditional solution is up-potting. You move each seedling into a larger container with fresh soil. It works, but it has real downsides:
- Root disturbance. Every time you pull a plant from its pot, you damage fine root hairs. Tomatoes recover well, but peppers and some herbs can stall for a week or more.
- Time. Moving 18 or 36 seedlings into new pots, filling with soil, watering in — it is an afternoon gone.
- Tray reorganization. Bigger pots need different trays and inserts. Your whole setup changes.
- Transplant shock. Even with careful handling, most plants show some stress after being moved.
The Alternative: Pot Extensions
This is where PlantSphere extensions come in. Instead of moving the plant to a bigger pot, you make the existing pot taller.
PlantSphere extensions are 3D-printed rings that snap directly onto Bootstrap Farmer 3.3" pots. You place the extension on top, add soil, and the plant keeps growing — roots undisturbed, same tray, same setup.
- Standard Extension — Adds ~2 inches of growing depth. Enough for another 2–3 weeks indoors.
- Tall Extension — Adds ~4 inches. For seedlings that are seriously overgrown or behind schedule.
They are made from food-grade PETG (the same material used in food containers), 3D printed in Toronto, and reusable season after season. You can find them at plantsphere.ca.
The key advantage is zero transplant shock. The plant never leaves its pot. You just give the roots more room to grow down, which is exactly what tomatoes want anyway.
Drainage and Watering Tips
Bootstrap Farmer pots have drainage holes, but how you water matters:
Bottom Watering
Most experienced growers bottom-water their seedlings. Fill the 1020 tray with water and let the pots wick it up from below. This encourages roots to grow downward and keeps the soil surface drier (reducing damping off).
Bottom watering works especially well with the 3.3" pots because they have enough depth for proper wicking.
Overwatering Signs
- Yellowing lower leaves
- Soil that stays wet for days
- Fungus gnats (they love wet surface soil)
If you are seeing these in the 2" or 2.5" pots, it might be time to move up to the 3.3" — more soil volume means more buffer for moisture.
How Long Do Bootstrap Farmer Pots Last?
The heavy-duty pots (3.3" and 5") are built to last multiple seasons. Growers regularly report using them for 3–5 years with no cracking or degradation. The key is cleaning them between seasons — a quick soak in diluted hydrogen peroxide kills any lingering pathogens.
The 2" and 2.5" inserts are thinner plastic and may last 2–3 seasons with careful handling.
Frequently Asked Questions
How many 3.3" pots fit in a 1020 tray?
With a Bootstrap Farmer tray insert, you can fit 18 of the 3.3" pots in a standard 1020 tray. A half-tray insert holds 9.
Can I use Bootstrap Farmer pots with other brands of trays?
Yes — the 1020 tray size is an industry standard. Bootstrap Farmer pots will fit in any standard 1020 tray. However, the tray inserts are specifically designed for Bootstrap Farmer pot dimensions.
What is the difference between Bootstrap Farmer 2.5" and 3.3" pots?
The 2.5" pots are 3" tall seed-starting pots with ¼" drainage holes, meant for the first few weeks. The 3.3" pots are heavy-duty, 4.3" tall (nearly 50% deeper), with a 0.62" drainage hole, and designed for growing seedlings for several weeks before transplanting.
Are Bootstrap Farmer pots food-safe?
They are made from polypropylene (PP #5), which is considered food-safe. This matters if you are growing edible crops.
Do I need tray inserts?
Technically no, but practically yes — especially with the 3.3" pots. Without inserts, pots will slide and tip when you move the tray. With extensions adding height, inserts become essential.
What is the difference between the 72-cell tray and the 72-cell air prune tray?
The standard 72-cell has cells that are 1½" square and 2¼" deep. The air prune version has slightly smaller cells (1.37" at the top, tapering to 1" at the bottom) at 2.29" tall, with slits that allow air to reach the roots. The air prune version prevents root circling, so plants can stay in the tray longer without becoming root-bound.
Summary: Which Pot When
| Situation | Pot Size |
|---|---|
| Germination / first 2 weeks | 32-cell tray (2" cells) or 2.5" pots |
| Seedlings for 3–6 weeks indoors | 3.3" heavy duty |
| Seedlings stuck indoors longer | 3.3" + PlantSphere extension |
| Up-potting for extended indoor growing | 5" square or 4-cell air prune insert |
| High-volume starts | Cell trays (72, 128, or 200 cell) |
| Growing lettuce to maturity | 2.5" pots |
| Container gardening outdoors | Grow bags (7–25 gal) |
| Raised bed alternative | Grow bags (100–200 gal) |
The 3.3" pot is the sweet spot for most home growers. It gives you enough depth for serious root development, fits neatly in 1020 trays, and with a PlantSphere extension, you can stretch its usefulness even further without having to transplant.
Start your seeds right. Browse PlantSphere extensions for Bootstrap Farmer 3.3" pots →