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Dracaena is one of the few common houseplants that is genuinely sensitive to fluoride, and to the boron and soluble salts that come with softened or heavily treated tap water. The damage shows at the very end of the leaf, because that is where the plant's transpiration stream finally deposits what it cannot use.
The pattern is distinctive once you know it. A fluoride or salt tip is dry, papery and tan to dark brown, with a narrow yellow band between the dead tissue and the healthy green. It stops there and does not spread through the leaf. Damage that spreads inward as a soft brown patch is a different problem, usually rot at the roots.
| What the tip looks like | Most likely cause | What to do |
|---|---|---|
| Dry tan tip, thin yellow halo, sharply defined | Fluoride or salts in the water | Switch water source and leach the pot |
| Tip and edge brown, whole leaf limp | Roots damaged by staying wet | Stop watering, check the roots |
| Tip brown, lower leaves yellowing fast | Fertilizer salts built up in the compost | Flush thoroughly, stop feeding for two months |
| Tip brown only on leaves near a vent | Hot dry air blowing on the plant | Move it out of the airflow |
A tip that has already gone brown will not turn green again. Judge whether you have fixed the problem by looking at leaves that open after the change, not at the old ones.
Change what you water with
This is the single change that fixes most dracaena tip burn, and it costs nothing to test. Give the plant a different water for two or three months and compare the new leaves with the old ones.
- Use rainwater or distilled water Rainwater and distilled water carry essentially no fluoride and no salts, and they are the reliable fix. Collecting a couple of gallons off a downpipe is enough to keep several plants going through a season.
- Standing tap water does not remove fluoride Leaving water out overnight lets chlorine gas off, which is worth doing, but fluoride is a dissolved salt and stays exactly where it was. Do not expect standing water alone to solve tip burn.
- Avoid softened water entirely A domestic softener replaces calcium with sodium, and sodium is worse for a dracaena than the hardness it removed. If your house is softened, take water from an unsoftened outside tap.
- Check what is in your supply Water suppliers publish fluoride levels. Above about 0.5 parts per million is enough to mark a dracaena over time, and most fluoridated supplies sit above that.
Flush the salts that are already there
Every watering leaves a little behind, so over a year or two the compost accumulates far more salt than any single watering contains. Flushing, or leaching, washes that out, and it is worth doing every three to four months on a plant that has been fed regularly.
- Take it to a sink or outside Move the plant somewhere the water can run away freely. Flushing into a saucer just redissolves the salts and pulls them back up into the pot as it dries.
- Pour slowly and repeatedly Run water through the compost at roughly four times the pot's volume, slowly enough that it soaks rather than channels. For an eight inch (21 cm) pot that is about a gallon and a half (six liters).
- Let it drain fully Give it an hour to stop dripping before it goes back on its saucer. The compost will be saturated, so the next watering is further away than usual.
- Scrape off white crust A white or yellowish crust on the compost surface or around the rim is crystallized salt. Scrape the top half inch (1 cm) off and top up with fresh compost.
Do not flush and feed in the same month. The point is to lower the salt concentration, and fertilizer puts it straight back.
How often to water
Dracaena stores water in its cane and copes with drying out far better than with staying wet. Let the top third of the pot dry before you water again, and go by weight rather than by a day count.
| Season | Room temperature | Interval | How to water |
|---|---|---|---|
| Spring | 61 to 75F (16 to 24C) | Every seven to ten days | Until it runs from the bottom, then empty the saucer |
| Summer | Above 75F (24C) | Every five to eight days | Morning, and flush thoroughly once in the season |
| Autumn | 59 to 70F (15 to 21C) | Every ten to fourteen days | Stretch the interval as the light weakens |
| Winter | 54 to 64F (12 to 18C) | Every three to four weeks | A mild morning only. Reduce frequency, not volume |
A plant in a low light corner uses a fraction of the water of one at a window. If you move a dracaena somewhere darker, lengthen the interval on the same day.
Telling too much from too little
The symptoms overlap enough that people water a rotting plant more, which finishes it. Push a finger two inches (5 cm) into the compost before you decide anything.
| Symptom | If the compost is wet | If the compost is dry |
|---|---|---|
| Lower leaves yellow and drop | Overwatered. Let it dry right out | Normal shedding, or long term underwatering |
| Leaves soft and folded lengthways | Roots failing | Thirsty. Water and it recovers within a day |
| The cane feels soft when squeezed | Stem rot. Cut back to firm tissue | Cannot happen when dry, check the compost again |
| A sour smell from the pot | Anaerobic compost. Repot into fresh | Not a watering issue |
Write down the date you switched water source and the date of each flush. When new leaves come clean six months later, you will know which change did it.
Lucky bamboo grown in water
The canes sold as lucky bamboo are a dracaena, and they show tip burn faster than any potted one because the roots sit permanently in the water you give them. Everything dissolved in that water stays in contact with the roots until you change it.
Change the water completely every week or two rather than topping it up, and use rainwater or distilled water. Topping up concentrates the salts as the water evaporates, which is why a cane that was fine for a year suddenly browns at every tip.