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If you own an AeroGarden and you’ve read our AeroGarden Replacement Pods guide, you already know that the cheapest commercial replacement option (Growell or Yoocaa universal sponges) lands at roughly $0.30 per pod. That’s already 84% cheaper than the legacy AeroGarden Grow Anything kits when those were in stock — but if you’re a serious DIY person, you can go significantly cheaper still by making your own pod sponges from raw materials.
This guide covers three DIY methods that actually work in a standard AeroGarden Bounty, Harvest, Sprout, or any other system using round pod baskets: rockwool cubes, coco coir, and reused K-cup coffee pods. We’ll cover the materials, the step-by-step procedure for each, the cost-per-pod math, and the honest case for which method is right for which kind of grower — including the contrarian answer that for most casual AeroGarden owners, DIY isn’t actually worth the labor savings, and you should buy commercial universal sponges instead.
If you want a structured side-by-side decision before reading the full procedures, jump to the comparison table and the bottom line sections at the end.
TL;DR
| Method | Cost per pod | Effort per pod | Best for |
|---|---|---|---|
| Rockwool 1” cubes | ~$0.08-0.12 | 5-10 min (first time) / 2-3 min (after) | Most DIY growers — best balance of cost, performance, and simplicity |
| Coco coir | ~$0.05-0.10 | 5-7 min | Growers who already have coco coir from soil/container gardening; not first choice for AeroGarden specifically |
| Reused K-cup coffee pods | ~$0.02-0.05 | 8-15 min | Coffee drinkers with a backlog of used K-cups, casual experimenters, “use what I have” growers |
| Commercial universal sponges (for comparison) | ~$0.30 | 0 min (no prep) | Casual AeroGarden owners who value time over cost savings |
Check Price · Check Price · Check Price · Check Price
The honest one-line answer: for most AeroGarden owners, the right move is to buy a $18 Growell 120-piece universal sponge kit ($0.30 per pod, zero prep time) and use that as your default pod source. Use DIY methods only if (a) you’re growing 50+ pods per year and the labor savings actually compound, (b) you want a specific seed variety that doesn’t come pre-seeded in any commercial kit, or (c) you genuinely enjoy the DIY craftiness aspect of the hobby. The cost savings of DIY are real but small in absolute dollars for a casual grower — saving $0.20 per pod times 30 pods per year is only $6 per year.
We’ll explain the reasoning in detail below, but if you’re looking for the contrarian answer: commercial sponges win for most buyers, and the DIY methods in this guide are mostly for serious hobbyists, not for the average AeroGarden refugee.
Before You Start: What You Already Have
Almost every AeroGarden owner already has the most expensive part of a DIY pod: the plastic grow basket and the clear grow dome from the original AeroGarden seed pod kits. These parts are reusable indefinitely. If you’ve been throwing away your used AeroGarden pods at the end of each growing cycle, stop doing that and start saving the baskets and domes — it’s the difference between a $0.10 DIY pod and a $0.50 DIY pod.
The reusable parts to save:
- Grow basket — the small white perforated plastic cup that holds the sponge and the seedling
- Grow dome — the clear plastic dome that goes over the basket during germination
- Pod label — the white sticker tab on top of the dome (optional, but useful for tracking what’s planted where)
Wash these parts with mild soap and water between plantings, check for cracks, and replace only if they’re physically damaged. A grow basket with a small crack still works fine; one with a big crack will let the sponge fall through into the reservoir and is the only reason to replace it.
If you don’t have any saved grow baskets (you’re new to AeroGarden or you’ve already thrown away your originals), you can buy replacement baskets in bulk on Amazon for roughly $0.10-0.15 per basket. The same Growell and Yoocaa universal kits that sell sponges also sell empty grow basket + grow dome kits at the same per-unit cost.
Method 1: Rockwool Cubes (Recommended)
Cost per pod: ~$0.08-0.12 Time per pod: 5-10 min first time, 2-3 min after Difficulty: Easy
This is the recommended DIY method for AeroGarden replacement pods. Rockwool is the standard hydroponic substrate used in commercial greenhouse production worldwide, it’s specifically engineered for water-based root growth, it produces germination rates and growth performance comparable to commercial sponges, and the per-pod cost is among the lowest of any DIY method.
What you need
- 1-inch rockwool cubes — sold in sheets at most hydroponic retailers and on Amazon. A standard sheet of 200 cubes runs roughly $15-18, which works out to about $0.08 per cube. The cubes are typically pre-scored for easy separation but you may need to gently snap them apart. (Check Price)
- pH-balanced water — rockwool naturally has a high pH (8.0+) when dry, which needs to be neutralized before use. You’ll soak the cubes in pH-balanced water (5.5-6.5) for at least an hour before planting. This step is non-negotiable — skipping the pre-soak is the most common rockwool failure mode.
- Reused AeroGarden grow baskets — see the previous section
- Reused AeroGarden grow domes — see the previous section
- Your own seeds — any variety that grows in standard AeroGarden conditions
- pH down solution (food-grade phosphoric acid, ~$10 from any hydroponic retailer) — needed if your tap water is alkaline
- A clean container for soaking the cubes
Step-by-step procedure
Step 1 — Prepare the soaking water. Fill a clean container with enough water to fully submerge however many rockwool cubes you’re preparing. Use distilled water if possible (tap water in many areas is alkaline and complicates the pH balancing). Test the pH of the water with a pH meter — it should read between 5.5 and 6.5. If it’s higher than 6.5 (which is typical for tap water), add a few drops of pH down solution and re-test until you’re in range.
Step 2 — Soak the cubes. Drop the rockwool cubes into the pH-balanced water and let them soak for at least 1 hour, ideally 2-4 hours. The cubes should be fully saturated and sink to the bottom of the container. Don’t compress or squeeze the cubes during soaking — let the water absorb naturally.
Step 3 — Test the post-soak pH. Pull a cube out and squeeze a few drops of water from it onto your pH meter. The water coming out of the cube should now be in the 5.5-6.5 range. If it’s still above 7.0, the cube didn’t fully neutralize — soak for another 1-2 hours. The pre-soak pH balance is the most common DIY rockwool failure cause, and it’s worth checking the first few cubes carefully until you’ve calibrated your soaking routine.
Step 4 — Place the cube in the grow basket. Pull a saturated cube from the soaking water and gently place it into a clean reused AeroGarden grow basket. The cube should fit snugly but not be compressed — don’t force it. The cube will stick up slightly above the top of the basket, which is normal.
Step 5 — Plant the seed. Use a toothpick or the tip of a pencil to make a small indent in the center of the cube, about 1/4 inch deep. Drop your seed into the indent. For most herb and leafy green seeds, plant 2-3 seeds per cube and thin to the strongest seedling after germination. For larger seeds (cucumber, mini tomato), plant 1-2 seeds per cube.
Step 6 — Cover with the grow dome. Place the clear reused grow dome over the basket. The dome maintains humidity during germination, which significantly improves the germination rate.
Step 7 — Drop the basket into your AeroGarden as normal. Place the basket in any pod position in your AeroGarden. Add your normal nutrient solution to the reservoir at the recommended dose. Set the light cycle as you normally would. Germination should occur within 3-7 days for most crops.
Step 8 — Remove the grow dome after germination. Once the seedling has emerged and pushed against the dome (typically 5-10 days after planting), remove the dome to give the seedling room to grow. Save the dome for your next planting.
What can go wrong
- Skipping the pH pre-soak. This is the #1 rockwool failure cause. Rockwool fresh out of the bag has a pH around 8.0+, which kills seedlings. Always pre-soak in pH-balanced water for at least 1 hour.
- Compressing the cube too tightly into the basket. Compression reduces oxygen in the root zone and can cause damping-off in seedlings.
- Using the wrong cube size. 1-inch cubes are the right size for AeroGarden grow baskets. 1.5-inch cubes are too big and won’t fit; smaller cubes are too small and won’t hold the seedling stable. Always buy 1-inch cubes specifically.
- Soaking the cubes too long. Anything longer than 24 hours risks anaerobic conditions in the cube, which damages the structure and causes root rot in seedlings. 1-4 hours is the right window.
Why we recommend rockwool over the alternatives
Rockwool is the best balance of cost, performance, and simplicity for DIY AeroGarden pods. The per-pod cost is among the lowest of any method (~$0.08-0.12), the germination performance is comparable to commercial sponges, the workflow is straightforward once you’ve done it a few times, and rockwool is widely available at any hydroponic retailer or on Amazon. For first-time DIY pod makers, this is the right method to start with.
Method 2: Coco Coir
Cost per pod: ~$0.05-0.10 Time per pod: 5-7 min Difficulty: Easy-Medium
Coco coir is shredded coconut husk fiber, sold in compressed bricks that expand dramatically when wetted. It’s the cheapest credible substrate for DIY pods if you already have a brick of coco coir from soil/container gardening — but it has practical drawbacks for AeroGarden specifically that make it our second-place DIY method rather than our first.
What you need
- Coco coir brick — sold at garden centers, hydroponic retailers, and Amazon for roughly $5-15 per brick. A standard 1.4 lb compressed brick expands to roughly 8 quarts of loose coco coir, which is enough for hundreds of DIY pods. (Check Price)
- Reused AeroGarden grow baskets and grow domes
- Your own seeds
- pH-balanced water (same as rockwool method)
- A clean container for hydrating the coco coir
Step-by-step procedure
Step 1 — Hydrate the coco coir brick. Place the brick in a large container and pour pH-balanced water over it. Wait 10-20 minutes for the brick to fully expand. The expansion is dramatic — a 1.4 lb brick expands to about 8 quarts of fluffy coco coir. You only need a small handful for DIY pod making, so most of the expanded coir will go into your other gardening uses.
Step 2 — Test the pH. Coco coir has a more neutral pH than rockwool (typically 5.5-6.8 out of the bag), so the pre-soak pH balancing is less critical than for rockwool. Test the hydrated coir with a pH meter to confirm it’s in the 5.5-6.5 range.
Step 3 — Pack the coco coir into the grow basket. Take a small handful of moist coco coir and gently pack it into a clean reused AeroGarden grow basket. The coir should be moist but not dripping, packed firmly enough that it stays in the basket but loose enough that water can flow through. Don’t compress the coir too tightly — this is the most common coco coir failure mode for AeroGarden specifically.
Step 4 — Plant the seed. Same as the rockwool method — make a small indent, drop the seed, cover with a tiny pinch of additional coir.
Step 5 — Cover with the grow dome. Same as rockwool.
Step 6 — Drop the basket into your AeroGarden. Same as rockwool.
Why coco coir is our second-place DIY method (not first)
Coco coir works in an AeroGarden but has two practical drawbacks:
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The coir compacts over time and reduces root oxygenation. Rockwool maintains its structure and water-air ratio across the entire grow cycle; coco coir tends to settle and compress, especially in the constant-moisture environment of an AeroGarden reservoir. This reduces oxygen in the root zone and can stunt plant growth in the second half of the grow cycle. We’ve seen reduced yields on tomato and pepper crops in our coco-coir DIY pods compared to rockwool.
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The coir can wash out of the grow basket. AeroGarden grow baskets have slits in the sides (designed for the original dense sponge format), and loose coco coir can wash through those slits over weeks of constant water flow, leaving the seedling roots exposed and the basket partially empty. Rockwool cubes don’t have this problem because they hold their shape.
Coco coir is the right choice if you already have a brick of coco coir from other gardening uses and you don’t want to buy a separate hydroponic substrate, or if you’re price-sensitive enough that the marginal cost difference matters. Otherwise, rockwool is the better DIY substrate for AeroGarden specifically.
Method 3: Reused K-Cup Coffee Pods
Cost per pod: ~$0.02-0.05 Time per pod: 8-15 min Difficulty: Medium
This is the most cult-favorite DIY method on hydroponic forums, popular for its “use what you have” appeal: if you’re a regular coffee drinker with a Keurig or similar K-cup machine, you have a steady supply of small plastic cups with built-in drainage. Used K-cups can be cleaned, modified, and used as DIY hydroponic pod containers in an AeroGarden — replacing both the grow basket AND the substrate in one step.
What you need
- Used K-cup coffee pods — preferably emptied of coffee grounds and rinsed, with the foil lid removed. Standard Keurig K-cups, Nespresso compatible cups, and most other single-serve coffee pod formats work, but the dimensions vary by brand and you’ll need to test fit before committing. Standard Keurig K-cups are very close in size to a standard AeroGarden grow basket.
- A small amount of soilless growing medium — coco coir, perlite, vermiculite, or even shredded paper. You’re using a small handful per K-cup just to give the seedling something to root in.
- Your own seeds
- A drill, awl, or sharp knife for adding additional drainage holes to the K-cup if needed
Step-by-step procedure
Step 1 — Empty and clean the K-cup. Pull the foil lid off the used K-cup. Empty the spent coffee grounds (compost them — they’re great for outdoor garden soil). Rinse the cup thoroughly with hot water to remove residual coffee oils. The interior should be clean enough that there’s no visible coffee residue.
Step 2 — Check the existing drainage hole. Most K-cups have one small drainage hole punched in the bottom for the brewing process. You’ll need additional drainage holes for hydroponic use — typically 4-6 small holes around the bottom and lower sides. Use a drill, an awl, or a sharp knife to add holes, being careful not to crack the cup.
Step 3 — Test fit in your AeroGarden. Drop the modified K-cup into one of the AeroGarden pod positions. The fit varies by K-cup brand: standard Keurig K-cups are very close to the right size but typically sit slightly deeper than the original AeroGarden grow basket. This is usually fine, but check that the cup doesn’t fall through the pod position entirely. If the K-cup is too small, wrap a thin strip of plastic or foil around the rim to increase the diameter.
Step 4 — Add the growing medium. Fill the K-cup with a small amount of moist soilless growing medium — coco coir works best, perlite-vermiculite mixes work, even shredded paper works in a pinch for fast-growing herbs. Don’t pack it too tightly. The medium should fill the cup most of the way without being compressed.
Step 5 — Plant the seed. Same as the other methods — small indent, drop the seed, cover with a tiny pinch of medium.
Step 6 — Cover with a grow dome (if your K-cup is small enough). Standard AeroGarden grow domes will fit over most K-cups but the fit is loose. Some K-cup users skip the dome entirely and rely on the AeroGarden’s enclosed environment for humidity. Both approaches work for most herb and lettuce seeds.
Step 7 — Drop into the AeroGarden as normal.
Why K-cups are the niche method
K-cups are the cheapest possible DIY method if you measure cost only in dollars per pod (literally free if you’re a coffee drinker), and they have a strong “I made this from trash” aesthetic appeal. But they’re also the most labor-intensive method, the fit varies by K-cup brand, and the growing performance is meaningfully worse than rockwool because K-cups have less surface area and worse oxygenation than purpose-built hydroponic substrate.
K-cups are the right choice if:
- You’re a regular coffee drinker with a backlog of used K-cups already accumulating
- You enjoy the “upcycled trash into garden” craftiness aspect of DIY hydroponics
- You’re willing to accept somewhat lower yields and somewhat higher labor in exchange for nearly-free pods
- You’re growing fast crops (lettuce, basil, microgreens) where a slightly compromised root environment doesn’t matter much
K-cups are NOT the right choice if:
- You want maximum yield from your AeroGarden
- You’re growing fruiting plants (tomato, pepper) that need optimal root conditions
- You don’t already have a backlog of used K-cups (the time cost of collecting them isn’t worth the marginal savings vs rockwool)
For most readers, rockwool is a meaningfully better DIY method even though it costs more per pod ($0.08-0.12 vs $0.02-0.05). The K-cup method is a niche curiosity, not a primary recommendation.
DIY Pod Method Comparison
| Method | Cost / pod | Time / pod | Germination quality | Crop range | Best for |
|---|---|---|---|---|---|
| Rockwool 1” cubes | $0.08-0.12 | 5-10 min first / 2-3 min after | Excellent | Everything from herbs to tomatoes | Most DIY growers |
| Coco coir | $0.05-0.10 | 5-7 min | Good (compacts over time) | Herbs and leafy greens; less ideal for fruiting | Growers who already have coco coir |
| K-cup coffee pods | $0.02-0.05 | 8-15 min | Acceptable for fast crops | Lettuce, basil, microgreens; not for tomatoes/peppers | Coffee drinkers who enjoy upcycling |
| Commercial Growell sponges (for comparison) | $0.30 | 0 min | Excellent | Everything | Casual growers who value time over savings |
| Commercial Yoocaa all-in-one kit (for comparison) | $0.32 | 0 min | Excellent | Everything | First-time refill buyers wanting baskets + nutrients in one box |
When DIY Isn’t Worth It (The Honest Truth)
This is the section most DIY tutorials skip, and it’s the one most readers actually need.
The cost savings of DIY pods are real but small in absolute dollars for most casual AeroGarden owners. Let’s run the math for a typical Bounty owner who replants all 9 pods every 8 weeks (so 6 full plantings per year, or 54 pods per year):
| Method | Annual cost (54 pods) | Annual time investment |
|---|---|---|
| DIY rockwool | ~$5-7 | ~3-5 hours |
| DIY coco coir | ~$3-5 | ~3-4 hours |
| DIY K-cups | ~$1-3 | ~5-8 hours |
| Commercial Growell sponges | ~$16 | <30 min |
| Commercial LetPot pre-seeded refills | ~$108 | 0 min |
For a casual grower, going DIY rockwool instead of Growell sponges saves you about $11 per year — at the cost of 3-5 hours of additional labor per year. That works out to roughly $2-4 per hour of saved labor, which is well below minimum wage. For most casual growers, this is not a worthwhile trade.
DIY makes economic sense when:
- You’re growing 100+ pods per year — at that scale, the per-pod cost difference compounds and DIY can save $30-50/year in pure dollars.
- You want a specific seed variety that doesn’t come pre-seeded in any commercial kit — for example, a specific heirloom tomato variety, an unusual basil cultivar, or a microgreen species that no commercial brand sells.
- You enjoy the craftiness of DIY as part of the gardening experience — for some growers, making their own pods is part of the fun, and the labor isn’t really a “cost” because they’d be tinkering with the system anyway.
- You’re scaling beyond a single AeroGarden — operators of multiple smart gardens, vertical hydroponic towers, or grow tents have higher pod consumption that justifies the upfront DIY learning investment.
For everyone else — the casual AeroGarden Bounty owner replanting a handful of herbs every couple of months — buy the $18 Growell 120-piece kit and skip the DIY entirely. The labor savings are not worth the minor cost premium.
Frequently Asked Questions
Will any of these DIY pods work in non-AeroGarden systems?
Yes — any DIY pod that fits a standard round AeroGarden grow basket also fits the universal round-pod systems we cover in our AeroGarden replacement pods guide: LetPot, iDOO, Ahopegarden, MUFGA, URUQ, and most other Chinese-origin smart gardens. The only systems incompatible with these DIY methods are square-pod systems (some iDOO variants, the LYKO system) and proprietary-pod systems (Click & Grow Smart Soil, Gardyn yCubes).
Where do I source pH-balanced water if I don’t have a pH meter?
Distilled water at any US grocery store is your easiest answer. Distilled water has a pH right around 7.0 and is the standard recommendation for AeroGarden owners anyway (see our AeroGarden pH troubleshooting guide). For DIY pod soaking, distilled water is close enough to the target 5.5-6.5 range that the rockwool soak still works adequately even without precise pH adjustment. If you’re serious about hydroponic growing, you should have a pH meter anyway — the $35 entry-tier meter pays for itself the first time it catches a problem.
Can I reuse rockwool cubes after a grow cycle?
Generally no. Rockwool is a single-use substrate — once a plant has grown roots through the cube, you can’t really clean it for re-use without damaging the cube structure. Rockwool is cheap enough at ~$0.08 per cube that single-use is the right approach. Coco coir is technically reusable if you carefully remove the old roots and rinse the medium, but the labor isn’t worth the savings.
Are there safety concerns with rockwool?
Rockwool fibers can irritate skin and lungs if mishandled — it’s similar to fiberglass in that respect. Wear gloves when handling dry rockwool, and avoid breathing in dust from cutting or breaking cubes. Once the cubes are wet, the fiber shedding stops and the material is safe to handle bare-handed. Standard gardening gloves are fine for the dry handling step.
Can I use these DIY pods for tomato or pepper seeds?
Yes, with caveats. Rockwool works well for tomato and pepper seeds in an AeroGarden — germination rates are comparable to commercial sponges and the cube structure supports the slightly larger root systems of fruiting plants. Coco coir is acceptable but less ideal because the substrate compacts over the longer grow cycle of fruiting plants (10-16 weeks vs 4-8 weeks for leafy greens). K-cups are NOT recommended for fruiting plants — the limited root volume and oxygenation aren’t enough for tomato or pepper success.
For tomato and pepper-specific guidance, you may also want to consider stepping up from the AeroGarden’s small reservoir to a LetPot LPH-Max with the dual-deck fruiting tray or to a grow tent setup, both of which give fruiting plants more room than an AeroGarden can provide regardless of which pod substrate you use.
Where do I buy 1-inch rockwool cubes at the lowest price?
Hydroponic retailers like Hydrobuilder, HTG Supply, and PowerGrow Systems sell rockwool at the lowest per-cube prices (often around $0.06-0.08 per cube for sheets of 200+). Amazon prices are typically slightly higher (~$0.08-0.12) but the convenience and Prime shipping is usually worth the small premium for casual buyers. Local hydroponic stores have the highest per-cube prices but are useful if you want to buy a single sheet without shipping costs.
Can I make pre-seeded DIY pods to give as gifts?
Yes — this is actually one of the genuinely fun applications of DIY hydroponic pods. Pre-soak rockwool cubes, plant the seeds, place them in grow baskets with grow domes, label with the variety, and pack 6-12 in a small box with an instruction card. The recipient drops the pods directly into their AeroGarden, LetPot, or any compatible smart garden and starts growing. The total cost per gift (12 pods + box + label) is around $5, and it’s a more thoughtful gardening gift than yet another houseplant.
What about hemp wool or other alternative substrates?
Hemp wool is an emerging alternative to rockwool — it’s made from compressed hemp fibers and has similar water-air properties to rockwool with less irritating dust. We haven’t tested hemp wool extensively in AeroGardens but published reviews suggest it works comparably to rockwool with marginally better sustainability credentials. The cost per cube is currently 2-3x higher than rockwool, which is the main reason it’s not our default recommendation. If you specifically want a more sustainable substrate and you’re willing to pay the premium, hemp wool is worth investigating.
Can I use peat-based seedling plugs (Jiffy pellets) for AeroGarden?
Marginally. Jiffy pellets and similar peat-based seedling plugs are designed for soil transplanting, not continuous-water hydroponic systems. They can work in an AeroGarden as a DIY pod alternative, but the peat tends to hold too much water and reduce root oxygenation, which causes damping-off problems in seedlings and reduced yields in mature plants. Rockwool is meaningfully better for AeroGarden specifically even though the up-front cost is similar. Use Jiffy pellets only if you have a stash from outdoor seedling-starting and you want to use them up.
Is DIY actually the cheapest way to run an AeroGarden long-term?
Yes, in pure dollar terms — but the time cost matters. The cheapest dollar-per-pod path is DIY rockwool at ~$0.08-0.12 per pod, vs Growell commercial sponges at ~$0.30 per pod. The cheapest time-adjusted path is commercial sponges, because the per-pod prep time of DIY pods (5-10 minutes) outweighs the per-pod cost savings for casual growers. The right answer depends on whether you value time savings or dollar savings more — and for most casual AeroGarden owners replanting a handful of pods every couple months, time savings matter more.
What if I want to grow microgreens specifically?
Microgreens are the one crop where DIY methods genuinely shine — the short growth cycle (7-14 days from seed to harvest) means you don’t need optimal root conditions, the dense planting density means each “pod” hosts dozens of seeds, and the per-tray cost matters more than per-pod cost because microgreen growers replant constantly. For microgreens specifically, look at flat-tray systems with hemp mats, coco mats, or even paper towels rather than the AeroGarden pod format. We have a forthcoming microgreens guide that’ll cover that workflow in detail.
Bottom Line
For most AeroGarden owners reading this guide, the right answer is to skip DIY entirely and buy commercial Growell or Yoocaa universal sponges at ~$0.30 per pod. The labor savings of DIY are real but small in absolute dollars, and most casual growers will find that 5-10 minutes of pod prep per planting isn’t worth $0.20 per pod in savings.
For serious DIY growers, growers running multiple systems, or anyone replanting 100+ pods per year, the cost math flips in favor of DIY. In that case, rockwool 1-inch cubes at ~$0.08-0.12 per pod are the recommended method — they have the best balance of cost, performance, and simplicity, the workflow is straightforward once you’ve done it a few times, and the substrate is widely available at any hydroponic retailer or on Amazon.
Coco coir is a credible alternative if you already have a brick from other gardening uses, but the substrate’s tendency to compact over time and wash out of grow baskets makes it our second-place DIY method for AeroGarden specifically. Reused K-cup coffee pods are a fun niche method for coffee drinkers who enjoy the upcycled-trash craftiness aspect, but the limited root volume and oxygenation make them poor for anything beyond fast-growing herbs and leafy greens.
The full DIY starter kit for rockwool method is approximately:
- 1-inch rockwool cubes (200-cube sheet) — ~$15-18 (buy)
- pH down solution — ~$10
- Replacement grow baskets (if you don’t have saved AeroGarden originals) — ~$8 for a pack of 30
- A pH meter (entry-tier $35) — recommended even outside the DIY context
Total starter cost: about $65-70, which gets you the supplies for roughly 200 DIY pods. At ~$0.10 per pod that’s a 5-year supply for a typical AeroGarden Bounty owner.
If you’d rather skip the DIY workflow entirely, our full AeroGarden Replacement Pods guide covers all the commercial pod options including LetPot pre-seeded refill kits, Growell universal sponge kits, and Click & Grow’s premium subscription model — most of which are the right choice for most casual growers.
Methodology note. This guide is based on hands-on use of rockwool 1-inch cubes in an AeroGarden Bounty across multiple grow cycles. Coco coir and K-cup methods are based on aggregated owner reports from r/aerogarden, the AeroGardenAddicts forum, and published DIY tutorials cross-referenced against our own limited testing of each method. Cost estimates reflect current retail prices for the substrates and accessories listed, and may vary based on bulk purchasing and regional availability. Read our full testing methodology.
Last verified pricing: 2026-04-08. Report a stale price.
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