Getting it to bloom
Why won't my Cross Gentian bloom? (and how to make it flower)
Also called Cross gentian, star gentian, Blue Cross gentian (Gentiana cruciata).
More about cross gentian
About Cross Gentian
Gentiana cruciata · also called Cross gentian, star gentian · flowering
Gentiana cruciata is a robust, clump-forming herbaceous perennial native to calcareous grasslands, woodland margins, and rocky slopes across Europe and western Asia, from Spain to Siberia. It bears clusters of deep mid-blue, four-lobed tubular flowers in whorls along upright leafy stems throughout summer and early autumn, and is notable as one of the easiest gentians to grow, tolerating a wider range of soils and drier conditions than most of the genus. The single most important care fact is that it prefers well-drained conditions and dislikes heavy, waterlogged soils — unlike many other gentians it is relatively drought-tolerant once established. This species is not known to be toxic to cats and dogs.
Plant type: flowering
Watch for — Aphid infestation: Clusters of aphids can infest the soft growing tips and flower stems in spring and early summer; knock off with a strong jet of water or apply an insecticidal soap spray, avoiding chemical insecticides that harm pollinators.
The reasons cross gentian isn't blooming
Almost every non-blooming cross gentian traces back to one of these, roughly in order of how common they are:
- Too little sun — most of these need full sun (or very bright light) to flower well; shade gives leaves, not blooms.
- Too much nitrogen feed, driving lush foliage at the expense of flowers (very common with general or lawn feeds).
- The plant has not been deadheaded, so it stops flowering once it sets seed.
- Irregular watering — drought or waterlogging at the budding stage makes buds abort.
- It is still too young or was checked by a transplant and is rebuilding before flowering.
Feeding cross gentian a high-nitrogen general feed and growing it in too little sun — you get a big leafy plant and almost no flowers.
The fix — how to get cross gentian to flower
- Maximise sun. Give cross gentian the sunniest spot you have — for most bedding and fruiting plants, more direct light directly means more flowers.
- Switch the feed. Move off high-nitrogen feeds and use a higher-potassium "bloom" or tomato-type feed as it comes into flower.
- Deadhead regularly. Remove spent flowers often to keep it producing more rather than stopping to set seed.
- Water consistently. Keep moisture even through budding and flowering — drought-then-flood swings make buds drop.
Light and feeding do most of the heavy lifting here. Dial in the spot with the light guide for cross gentian and get the feeding right with the cross gentian fertilising schedule — the wrong feed (too much nitrogen) is one of the most common silent reasons a healthy plant makes leaves instead of flowers.
Bloom season and what to expect
Cross Gentian flowers across its growing season (mostly summer) and, kept fed and deadheaded, can bloom for many weeks or right up to frost.
Post-bloom care so it flowers again
Deadhead, keep feeding lightly, and many will rebloom; collect seed from the best plants at the end of the season if you want to grow them again.
For everything else this plant needs day to day, see the full cross gentian care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.
Cross Gentian blooming — frequently asked questions
Why won't my cross gentian flower?
Cross Gentian blooms on the season's growth given enough sun, warmth and the right feed — there is no cold or photoperiod trick, just good growing conditions and a bloom-leaning feed. The most common reason it is not happening: Too little sun — most of these need full sun (or very bright light) to flower well; shade gives leaves, not blooms.
How do I make cross gentian bloom?
Give cross gentian the sunniest spot you have — for most bedding and fruiting plants, more direct light directly means more flowers. Move off high-nitrogen feeds and use a higher-potassium "bloom" or tomato-type feed as it comes into flower.
When does cross gentian normally bloom?
Cross Gentian flowers across its growing season (mostly summer) and, kept fed and deadheaded, can bloom for many weeks or right up to frost.
What should I do with cross gentian after it flowers?
Deadhead, keep feeding lightly, and many will rebloom; collect seed from the best plants at the end of the season if you want to grow them again.
What is the single biggest mistake stopping cross gentian flowering?
Feeding cross gentian a high-nitrogen general feed and growing it in too little sun — you get a big leafy plant and almost no flowers.
Keep reading
- Cross Gentian care — the full brief (light, water, humidity, problems, pet safety)
- Cross Gentian light needs — usually the first thing to fix for flowers
- Cross Gentian fertilising — the right feed for buds, not just leaves
- Should I water my plant? The simple check
- Why is my plant wilting? Wet vs dry
- Underwatered plant — signs and rehydration
- Why won't my peace lily bloom?
- Why won't my jade plant bloom?
- Why won't my tomato bloom?
- All 4114 bloom guides in the Growli library