GardenAnnual Herb · 2 varieties
Borage
Borago officinalis
Boraginaceae — the only crop in its plant family here.
Borage (Borago officinalis) is an annual herb. It wants full sun and pH 6–7 soil, with about 0.5–1 in of water weekly. It matures in about 50–70 days from sowing, or 30–45 days from setting out a transplant. Watch for aphids and powdery mildew. Below: its full sourced profile from 7 extension sources, plus a planting calendar timed to your frost dates.
Typical dates for zone 6b — set your zone or ZIP for yours. This calendar assumes the crop is started indoors. Timing is a guide from the crop's sourced growth stages; confirm with your local frost dates and extension before you sow.
What we will not put a number on
We do not give a feeding rate for this crop, and that is deliberate rather than a gap. The figures published by extension services are pounds of nitrogen per acre for a production field — they do not convert safely to a raised bed or a pot without knowing your soil test and your fertilizer's analysis, and guessing errs toward burning roots. It is also why every chart you find online disagrees with the next one.
We give watering as a depth per week rather than gallons per plant, because that is how it is actually measured and how the published figures are written. A gallons-per-plant number depends on your spacing, your soil and whether the plant is in a pot — so it would look more precise than it is.
Site & soil
- Sun
- Full sun
- Soil pH
- 6–7est
- Soil texture
- Clay, Loam, Sandy, Well drained
- Frost tolerance
- Half hardyest
No published figure for the temperature frost starts to hurt it and the temperature that would kill it. We looked — where a number is missing here it is missing from the research, not skipped. The crop’s frost and heat tolerance above still applies.
The plant
- Mature height
- 1–3.2 ft
- Mature spread
- 9–18 in
- Growth rate
- Moderateest
- Spacing in row
- 12–15 in
- Between rows
- 18–24 in
- Planting depth
- 0.25–0.5 in
- Container size
- 3–5 gal — low end is the minimum, high end is betterest
- Support
- Needs staking or a trellis
- Grown from
- Direct sow, Transplant
Water & feeding
- Water needs
- Low
- Water per week
- 0.5–1 in/wkest
- Critical water
- Germination, Establishmentest
- Feeding
- Low
Timing & fruiting
- Days to maturity
- 50–70 days from seed · 30–45 days from transplantest
- Harvest cues
- First flowers
Planted again for autumn
- Set plants out by
- late Sep typical · zone 6b
30 days to maturity from setting a plant out — that is what our sources measure for this crop, so this is a date for planting out and not a sowing date, counted back from the first frost above. Not published for anywhere in particular: it is your own frost date and this crop's own figure, which is why it works wherever you are. A days-to-maturity figure is a catalog number for a good season rather than a promise, and a cold month moves it.
Edible parts per source: flower, leaf.
Compiled from the extensions cited below. Which ones actually show up depends on your region — your extension's local list is the last word.
Different parts differ — the edible part is the flower and leaf; the notes below flag other parts or preparations.
PeopleLow severity, Pyrrolizidine alkaloids, Liver damage
Petsdogs, cats, horses
Recorded exactly as the source states it — not medical or veterinary advice. If a person or animal may have eaten a toxic part, call Poison Control (1-800-222-1222) or your vet / the ASPCA line (888-426-4435).
| Variety | Habit | Days | Color | What it is known for |
|---|---|---|---|---|
| Common Heirloom | Spreading | 30–45 | Blue | NC State Extension records this asthe flowers are edible · draws bees and butterflies · drops seed and comes back on its own · grown for cooking |
| White Heirloom | Spreading | 30–45 | White | Select Seeds describes this asthe flowers are edible · draws bees and butterflies · drops seed and comes back on its own |
- ASPCA Animal Poison Control Center
- Johnny's Selected Seeds
- Missouri Botanical Garden
- NC State Extension
- University of Illinois Extension
- University of Maryland Extension
We compile bare facts from these university-extension and horticultural sources, never copied prose. 12 of the 19 values on this page carry a citation. The rest are marked est; hover one and it says why — either nobody publishes a figure we could point at, or a person set it and attached no source. Figures vary with climate and seed source; confirm with your local extension before you buy.
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