Scented geranium / Scented pelargonium (Pelargonium spp.) growing guide

Quick facts

Category: herbs woody
Difficulty: beginner
Days to harvest: 90 to 120 days
Harvest type: cut leaves, plant regrows for repeated harvests
Spacing: 45 cm between plants

Environment

Temperature: 10–28°C
pH: 6 to 7.5
EC (hydroponic): 1 to 1.6 mS/cm
Daily light: 14 to 22 mol/m²/day

Climate and zones

USDA zones: 9 to 11 (winter low around -7°C or warmer)
Frost tolerance: frost sensitive (dies at first frost)
Season: warm (summer crops, frost-sensitive)

Viable growing environments:

outdoor in growing season (annual)
unheated greenhouse / hoop house
heated greenhouse
indoor (heated home)

USDA zone bounds reflect outdoor year-round survival. Anywhere outside the bounded zone range, this crop still grows as an annual in the warm months (outdoor_seasonal), under cover (greenhouse), or indoors under lights.

Growing systems

Scented geranium works in:

drip / Dutch buckets
media bed (ebb and flow)
wicking bed
soil bed

Growing media

The substrate the roots sit in. Choice depends on the system (clay pebbles don't fit NFT channels; rockwool isn't used in media beds) and the crop (scented geranium works in the media listed below).

Medium	pH effect	Water retention	Bacterial surface
Expanded clay pebbles (LECA)	neutral / inert	low	high
Coco coir (Coconut coir)	slightly acidic	high	moderate
Perlite (Expanded volcanic glass)	neutral / inert	very low	low
Soil-based mix (Potting soil)	varies by source	high	high

Bacterial surface area matters for aquaponics: clay pebbles, lava rock, and pumice double as biofilter substrate. Low-surface media (rockwool, perlite, pea gravel) work in hydroponics but need a separate biofilter in aquaponics.

Nutrient demand by stage

NPK ratios are relative weights at each growth stage; the nutrient mix calculator scales them to absolute grams or ml. EC targets shift through the plant's life: seedlings need a much lighter solution than fruiting adults.

Stage	N	P	K	EC target (mS/cm)
seedling	1	1	1	0.6
vegetative	2	1	2	1.3

Aquaponics suitability

Not recommended for pure aquaponics. Fish waste alone doesn't provide enough of the nutrients this crop demands (typically potassium, calcium, or boron). It can be grown in a hybrid system where the reservoir is supplemented with hydroponic-style nutrients, but expect to dose actively.

Care notes

Easy container herbs for greenhouse or indoor growing. Container (10 L) with well-drained media. EC 1.0-2.0 mS/cm. pH 6.0-7.0. Temperature: 15–28°C (frost-sensitive). Moderate to high light (DLI 14-22 mol/m2/day). Growth is moderate. The plants become woody sub-shrubs (30–80 cm) over time and benefit from annual hard pruning in spring to keep them compact and bushy. Harvest leaves as needed for culinary use; the aroma is released by rubbing or bruising the leaf surface. For rose-flavored sugar: layer fresh rose-scented geranium leaves with granulated sugar in a sealed jar for 2-3 weeks. For cake: place leaves face-down in a buttered cake pan before adding batter; the fragrance infuses the cake during baking. Propagation by stem cuttings (root easily in moist perlite). The plants are long-lived and low-maintenance. A scented geranium collection is one of the most rewarding aromatic herb projects for a greenhouse or sunny windowsill.

Notable varieties

A starting shortlist of cultivars worth knowing about. Not exhaustive: the seed catalogs list hundreds of named varieties. These are the ones home growers commonly choose between.

Cultivar	Type	Notes
Rose (P. graveolens)	open-pollinated	The most-grown scented geranium and the source of geranium essential oil. Deeply cut grey-green leaves, strong rose-citronella scent. The variety to pick if you want one and only one; works for almost every culinary use the others do.
Lemon (P. crispum)	open-pollinated	Small crinkled leaves, sharp lemon scent. Compact upright habit, good in containers. The traditional variety for finger bowls; also makes a clean lemon syrup for cocktails and shortbread.
Peppermint (P. tomentosum)	open-pollinated	Large velvety soft leaves, distinct mint scent. Sprawling habit, good for hanging baskets. Less common in culinary use than rose or lemon but the textured foliage is striking.
Nutmeg (P. fragrans)	open-pollinated	Small grey-green leaves, warm spicy scent. The most compact of the common scented types. Used in baking syrups and infused sugars where a hint of nutmeg without the bite of the spice is wanted.
Apple (P. odoratissimum)	open-pollinated	Round soft leaves, sweet apple scent. Trailing habit; good in pots. Lighter, sweeter flavor than rose, pairs well with fruit jams and apple desserts.