Gadenin日本語Get the appAphids in the flowering tips
Aphids are by far the commonest problem, and they concentrate exactly where you least want them: packed into the flower buds and the soft growing tips. On a plant you are picking for tea this matters more than usual, because you cannot wash chamomile flowers without ruining them, so contaminated flowers are simply lost.
Catch them early. Turn over a growing tip every few days when you are picking and look for the small clusters of green or gray insects on the stem just below the buds. Sticky shine on the foliage, ants running up the stems, or sooty black mold on the leaves all mean the colony has been there a while and is already large.
- Squash the first colonies by hand A colony found at twenty insects is dealt with in ten seconds between finger and thumb. Left for a week it becomes several hundred spread over the whole plant, and at that point every option is worse.
- Pinch out badly infested tips Where a shoot tip is solid with aphids, cut it out entirely and put it in the bin rather than the compost pile. You lose a few flowers and stop the spread, which is a good trade.
- Do not spray a crop you are drinking Anything you spray onto flowers ends up in the tea, because the flowers cannot be washed. Rely on hand removal, on the ladybirds and hoverflies that arrive within a fortnight, and on stopping the conditions that caused it.
- Cut the nitrogen Aphid outbreaks follow soft nitrogen fed growth. If the plants are lush and dark green and repeatedly infested, the ground is too rich, and no amount of squashing will fix that this season.
Chamomile in flower attracts hoverflies, lacewings and ladybirds strongly, and an untreated aphid colony is usually cleaned up by them within two or three weeks. Reaching for a spray removes the predators as well and makes the next outbreak worse.
Thrips and the flowers that dry brown
Thrips are tiny, slim, dark insects that feed inside the flower head. The symptom is a flower that looks slightly silvered or bronzed on the petals, does not open cleanly, and dries a dull brown instead of white. Because they live inside the head you rarely see the insect itself; tap a flower onto a sheet of white paper and you will see them run.
Thrips build up in hot dry weather, particularly on plants that are drought stressed. Watering properly in a heatwave and picking off affected heads keeps it to a nuisance. It is rarely bad enough to lose a crop, but a run of brown drying flowers when the picking stage looked right almost always means thrips rather than a drying fault.
Powdery mildew and gray rot
Powdery mildew shows as a white dusty film on the leaves and stems, usually starting low down in the middle of the plant where the air is stillest. It arrives late in the season on plants that are crowded, in a sheltered spot, or being watered overhead in the evening. It does not usually kill the plant but it shortens the flowering run and the flowers get smaller.
Gray rot is the wet weather version: flowers and buds that turn brown, go soft and grow a gray fuzz, spreading from one head to its neighbors where they touch. Both are diseases of stagnant humid air rather than of infection arriving from outside, and both respond to the same handful of cultural fixes.
| Problem | Early sign | What to do |
|---|---|---|
| Powdery mildew | White dust on lower leaves | Thin the stand, cut out the worst growth, water at the base only |
| Gray rot on flowers | Brown soft heads with gray fuzz | Pick off and bin every affected head daily, improve airflow |
| Damping off in seedlings | Seedlings collapse at soil level | Sow thinner, keep the surface less wet, use fresh compost |
| Root rot | Whole plant yellows and wilts in wet soil | Improve drainage, raise the bed, stop watering |
Never compost mildewed or rotted chamomile from a bed you intend to sow again. Bin it. The spores overwinter perfectly well in a garden compost pile that never gets properly hot.
Damping off and slug damage in seedlings
The seedling stage is where chamomile is genuinely fragile. Damping off, a fungal collapse at soil level, takes out thickly sown surface sowings in a day or two, and it is caused by exactly the conditions that surface sowing tempts you into: a permanently wet surface, seedlings packed together, and no air movement. Sow thinner, mist rather than soak, and get the row cover off as soon as the seedlings appear.
Slugs and snails will graze a whole row of chamomile seedlings overnight and leave nothing to show for it, which people commonly misread as germination failure. If a sowing appeared and then vanished, look for slime trails at dawn before you blame the seed. Established plants are largely ignored, so the risk window is only the first three or four weeks.
- Check at dawn or after dark Slug damage is invisible in daylight because the animals are hidden. Go out with a torch after dark for two or three nights when a sowing first emerges and you will know immediately whether slugs are the cause.
- Clear the ground around the sowing Take away boards, dense weeds and loose mulch within a foot (30 cm) of the row while the seedlings are small. Removing the daytime shelter does more than anything you can put down.
- Do not water in the evening while seedlings are small A bed watered at dusk is exactly what slugs want and it also feeds damping off. Water in the morning so the surface is drier by nightfall.
Where trouble comes from, and what to record
Almost every chamomile problem on this list has the same three underlying causes: plants too close together, ground too rich, and foliage kept wet. If you find yourself dealing with several of these in one season, it is worth accepting that the bed itself is wrong rather than fighting each symptom separately. Moving the sowing to a leaner, sunnier, breezier position usually removes the whole set at once.
Keep a short note of the date you first saw each problem, which end of the bed it started in, and what the weather was doing. Aphids and mildew both arrive at a fairly consistent point in the season for a given garden, and once you have two years of first sighting dates you can start checking a week beforehand instead of finding the problem when it is already established.
Also record which bed the chamomile grew in. Chamomile is not badly affected by growing in the same ground repeatedly, but soil borne rots do build up on a wet site, and a three year rotation on record is far easier to keep to than one held in your head.