You know how many stems you need — for a wedding, a CSA, a market table. The harder question is how many plants to put in the ground to get them. Enter your stem goal for each variety below and this calculator returns the planting count, using real stems-per-plant yields for the crops flower farmers actually grow.
Planting plan · built free at getstemwise.com
For each variety, enter the stems you want this season. Yields are per plant, per season — edit by adding/removing rows.
Across 0 varieties.
Set your spacing and bed width — we'll turn the plant count into beds.
Tulips, stock and single-stem sunflowers give one cut each. Planting them all at once gives you one huge week and then nothing — so you split the same plant count into repeat sowings.
Want this planting plan in your inbox? We’ll email you the crop-by-crop list above — plant counts, stem goals and bed feet — so it’s on your phone when you’re standing in the field. The stems-per-plant yield table comes with it.
This tool tells you what to plant. Stemwise takes it the next step: it projects what your beds will actually cut each week, lines that up against everything you've promised across weddings, CSA and market, and hands you the shortfall to buy in and the surplus to push. That's the Sunday-night math the spreadsheets miss.
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Become a founding grower →It's the question every cut-flower grower runs into the first time they take a real order: how many plants do I need to get the stems I've promised? A florist asks for 150 stems of dahlias for a September wedding; a CSA needs 30 bouquets a week for 16 weeks. Stem goals are easy to write down — translating them into rows of plants and trays of seedlings is where most planting plans go wrong.
The math is simple once you know each crop's yield per plant: plants = stems needed ÷ stems per plant. The catch is that yield is a range, not a number — a dahlia might give you 8 stems in a cool, short season or 20+ in a long, warm one. This calculator plans to the low end of each range, so you don't come up short when the weather doesn't cooperate. A good season simply leaves you with surplus to sell at market.
These are realistic field yields for healthy, well-tended plants picked regularly through their productive window. Cut-and-come-again annuals are the workhorses; single-stem crops like tulips and single-stem sunflowers give one cut and are succession-planted instead.
| Variety | Stems / plant / season |
|---|---|
| Sweet pea | 30–50+ |
| Scabiosa | 15–25 |
| Gomphrena | 15–25 |
| Cosmos | 12–20 |
| Strawflower | 12–20 |
| Dahlia | 8–20+ |
| Anemone | 10–20 |
| Calendula | 10–20 |
| Yarrow | 10–20 |
| Eucalyptus (foliage) | 10–30+ |
| Zinnia | 8–15 |
| Ranunculus | 8–12 |
| Rudbeckia | 8–12 |
| Celosia | 6–12 |
| Snapdragon | 5–8 |
| Peony (mature) | 5–10 |
| Sunflower (branching) | 4–8 |
| Lisianthus | 4–8 |
| Amaranth | 4–8 |
| Sunflower (single-stem) | 1 (succession) |
| Tulip | 1 (succession) |
| Stock | 1 (succession) |
Want the full reference with productive windows and grower notes for 30+ crops? See our cut-flower yield-per-plant guide.
Under-planting is the expensive mistake. If you plan to the optimistic yield and the season runs cool, short, or buggy, you're suddenly buying in stems at wholesale to cover an order you already priced — wiping out the margin. Planning to the conservative yield costs you a little extra seed and bed space, and the downside is the best kind: surplus you can sell. That's why this calculator divides your stem goal by the low end of each plant's range.
A plant count on its own isn't yet a planting plan — two things turn it into one, and the calculator above now does both.
Spacing. Multiply plant counts by your in-row spacing to get bed feet. Set your spacing and bed width and the tool returns bed area, bed feet and rows across. The arithmetic is just geometry: a plant on a 9" grid takes 9 × 9 = 81 square inches, and a square foot is 144, so a 9" grid is about 1.8 plants per square foot — roughly 4 rows across a 3-foot bed. (Four plants per square foot is a 6" grid, not a 9" one; the two are easy to mix up.)
Succession. Single-cut crops — tulips, stock, single-stem sunflowers — give one stem and are then finished. You can't spread their harvest by cutting more often, only by sowing again, so their plant count is really a per-sowing count. Tell the tool how long a harvest window you want and how often you sow, and it splits the same plant total into repeat sowings. The count is a fencepost: sowings land on day 0, then every interval after, and the last must still fall inside the window — so an 8-week window sown every 14 days is 5 sowings (days 0, 14, 28, 42, 56), not 4. Cut-and-come-again crops like dahlias and zinnias need none of this; one planting produces all season. We stop short of printing sowing dates, because those depend on each crop's days to maturity — that number is on your seed packet, and we'd rather leave it there than guess it for you.
Both succession and spacing are exactly the kind of supply-side planning that feeds the weekly reconciliation in Stemwise.
Dahlias yield roughly 8–20+ stems per plant per season. If a wedding needs 150 dahlia stems, plan for about 19 plants at the conservative low yield (150 ÷ 8), or as few as 8 in a long, warm season. Because dahlias are tubers you keep year to year, planning to the high side once pays off for seasons.
A well-pinched, regularly-cut zinnia gives about 8–15 stems per plant over the season. For 200 stems, plan around 25 plants (200 ÷ 8). Zinnias are the classic cut-and-come-again workhorse — the more you cut, the more they branch.
Divide the stems you need by each crop's stems-per-plant yield, using the low end of the range so a slow season still covers you. Add succession plantings for single-stem crops, then multiply by spacing to get bed feet. That's the whole supply side of a flower-farm plan.
Work it out from your in-row spacing. A plant on a 9″ grid occupies 9 × 9 = 81 square inches, and a square foot is 144 square inches, so a 9″ grid holds about 1.8 plants per square foot — 500 plants needs roughly 280 square feet, or about 94 bed feet of 3-foot-wide bed, at 4 rows across. Tighten to a 6″ grid and you get 4 plants per square foot; open up to 12″ and you get 1. Add roughly 20% on top for paths and headlands. The calculator above does this arithmetic for your own numbers.
Count the fenceposts, not the gaps. Sowings land on day 0 and then every interval after, and the last one still has to fall inside your harvest window — so a window of W days sown every I days is (W ÷ I, rounded down) + 1 sowings. An 8-week window sown every 14 days is 5 sowings (days 0, 14, 28, 42, 56), not 4. Then divide your plant count between them: 500 tulip stems over those 5 sowings is 100 bulbs per sowing. Only single-cut crops need this — dahlias and zinnias produce all season from one planting.
That's the reconciliation problem, and it's where a planting calculator stops. Stemwise projects what each variety will actually cut week by week and lines it up against everything you've promised, so you see the shortfall to buy in and the surplus to sell before the week starts.