Greenhouse Inventory Checklist: 10 Must-Have Items for a Thriving Garden Today

Thin operating margins make inventory control mission-critical for greenhouse enterprises. University of Florida enterprise budgets for hydroponic tomatoes show negative net income once labor (18.6% of variable cost) and fixed overhead are included, even at $0.90 per pound pricing.[^1] If supplies, plants, and finished goods sit on the bench too long, the cash to cover labor, energy, and inputs disappears. This checklist turns your storage areas into a data source so you can align purchasing, production planning, and cash flow.

Key performance indicators to track alongside the checklist

| KPI | Formula | Why it matters | | ------------------------------ | ----------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Inventory turnover ratio | Cost of goods sold ÷ Average inventory value[^2] | Measures how often you sell through your stock. A low ratio signals excess inventory tying up cash or plant material aging past its prime. | | Inventory-to-sales ratio | Inventory value ÷ Monthly sales | U.S. retailers averaged ~1.3 throughout 2024, which equates to roughly 40 days of supply.[^3] Use this as an upper limit for durable goods; live plants should turn substantially faster. | | Inventory delta vs. net profit | (Ending inventory – Beginning inventory) compared with net profit | If inventory growth outpaces profit (common in greenhouse budgets[^1]), you are consuming cash even when the income statement looks positive. |

Inventory categories covered in the template

| Category | Examples | Tracking focus | | ------------------------- | -------------------------------------------------- | ---------------------------------------------------------------------------- | | Plant material | Seed, plugs, rooted cuttings, finished plants | Propagation date, supplier, variety, expected ship/pot-up date, loss factor. | | Growing media & nutrition | Potting mix, perlite, coco, fertilizers, injectors | Lot numbers, EC/pH specs, on-hand volume vs. reorder point. | | Packaging & merchandising | Pots, trays, tags, sleeves, retail signage | Seasonal demand spikes, supplier lead times, storage location. | | Infrastructure & tools | Benches, lights, sensors, sprayers, PPE | Service interval, calibration date, replacement cost, depreciation schedule. | | Consumables & utilities | Fuel, biological controls, sanitation chemicals | Safety stock, expiration date, regulatory documentation. |

Workflow for maintaining the checklist

1. Audit weekly during peak season. Integrate the walk-through with IPM scouting to minimise labor.
2. Reconcile quantities with production plans. Link tray counts and pot sizes to the crop schedule so you know when to reorder before a sowing or transplant window.
3. Capture shrink and spoilage. Log losses (disease, mechanical damage, expired inputs) separately from sales so you can target process improvements.
4. Sync with purchasing and accounting. Feed updated quantities into your purchasing system to prevent duplicate orders and to keep balance sheets accurate.

Template fields

| Field | Description | | -------------------------------- | --------------------------------------------------------------------------------------- | | Item/sku & category | Unique identifier and one of the categories above. | | Supplier & lead time | Supports reorder planning and vendor benchmarking. | | Unit of measure & reorder point | Allows conversion between vendor packs and daily usage. | | On-hand quantity & date verified | Ensures counts are current and timestamps audits. | | Unit cost & extended value | Provides real-time inventory valuation for financial statements. | | Storage location | Bench, cold room, chemical cabinet, etc., to speed picking. | | Status/condition | New, in use, needs repair, expired. | | Notes/actions | e.g., “Rotate stock—batch expiring 15 Aug,” or “Calibrate injector before poinsettias.” |

Cost-control levers to note during inventory checks

• Labor-saving automation. Michigan State University Extension highlights conveyors, transplanting equipment, and shipping tables as proven methods to reduce labor—the largest greenhouse expense.[^4]
• Energy efficiency. Record insulation, curtain systems, heater efficiency, and lighting upgrades as inventory line items. Knowing what you have lets you schedule maintenance that keeps energy use low.
• Product rationalisation. Use turnover data to prune slow-selling SKUs and focus on high-margin crops. Eliminating rarely ordered pot sizes or plant varieties frees cash and shelf space.
• Preventive maintenance. Logging service dates for irrigation injectors, sprayers, and fans reduces emergency repairs and unplanned downtime.

References

[^1]: Smith, J. L., Hewitt, T. D., Hochmuth, R. C., & Hochmuth, G. J. Enterprise Budget and Cash Flow for Greenhouse Tomato Production. University of Florida IFAS Extension (HS792). https://ufdcimages.uflib.ufl.edu/IR/00/00/09/83/00001/CV27000.pdf

[^2]: Investopedia. Inventory Turnover Ratio: What It Is, How It Works, and Formula. https://www.investopedia.com/terms/i/inventoryturnover.asp

[^3]: Federal Reserve Bank of St. Louis. Retailers: Inventories to Sales Ratio (RETAILIRSA). https://fred.stlouisfed.org/series/RETAILIRSA

[^4]: Lindberg, H. (2019). Decreasing Greenhouse Expenses. Michigan State University Extension. https://www.canr.msu.edu/news/decreasing-greenhouse-expenses