When to plant
Direct sow outdoors after last frost — does not transplant well (taproot). Germinates in 7–14 days. Fast growing and extremely productive. A warm-season annual killed by frost. Self-sows readily in mild climates. Blooms continuously from planting until frost.
Soil & site
Poor to average, well-drained soil — nasturtiums bloom most prolifically in poor, dry conditions. Rich or fertile soil produces lush, beautiful foliage with very few flowers. pH 5.5–7.5. No soil amendment needed.
Feeding
Avoid fertilizing — it dramatically reduces flower production in favor of leaves. The golden rule with nasturtiums: plant them where nothing else will grow and leave them alone.
Common problems
Aphids (particularly black aphids) love nasturtiums — this is sometimes intentional, as they are used as a trap crop to lure aphids away from other plants. Powdery mildew in late season. Flea beetles. Cabbage white butterfly larvae.
When to harvest
Flowers are ready as soon as they are fully open and vibrantly colored. Leaves can be harvested at any size — smaller leaves are more tender and milder. For seed pods (capers): pick when the seed pod is fat and green, before it starts to dry. For seeds: let pods dry on the plant until they turn tan and wrinkled.
How to harvest
Pinch flowers at their base. Snip leaves from the stem. For pickled nasturtium capers, harvest immature green seed pods immediately after the petals fall. Deadheading (removing spent flowers) extends the blooming period significantly. Seeds for replanting: let fully dry on the plant, then store in a paper envelope.
Storage & use
Flowers: use immediately — they wilt within hours once picked. Leaves: refrigerate for 2–3 days. All parts are edible and have a peppery, watercress-like flavor. Pickled seed pods substitute for capers. Flowers are excellent in salads, compound butters, and as a garnish.
Useful for growing nasturtium
A few things that make this one easier — chosen for this plant, not a generic list.
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