Gadenin日本語Get the appKeep the soil limy year after year
Liming once at sowing is not the end of it. Rain steadily washes calcium down through the soil, and on ground that is naturally acid the pH creeps back down within two or three years. A perennial plant that flowered beautifully in its second and third summer and then went sullen and yellow in its fourth is usually telling you the lime has gone, not that it is old.
Test the pH every second autumn and scatter garden lime on the surface around established plants if it has fallen below about 6.8, at a light rate of a handful per square yard, watered in. Do not dig it in around a perennial; the taproot and the fine surface roots both resent disturbance and surface applied lime moves down perfectly well on its own.
Yellowing between the veins on otherwise healthy looking growth is the classic signal of soil turning acid under a gypsophila. It looks like a nutrient deficiency, and in a sense it is, but the answer is lime rather than fertilizer. Adding feed to an acid soil makes the plant grow softer without fixing anything.
| What you see | What it means | What to do |
|---|---|---|
| Pale yellow leaves, weak growth on old plants | Soil has turned acid again | Surface lime in autumn, do not dig it in |
| Lush blue green leaves, very few flowers | Too much nitrogen | Stop feeding entirely; never mulch with compost |
| Sudden collapse of a whole plant | Crown or root rot from wet soil | Pull it; improve drainage before replanting |
| Steady growth, heavy flowering, wiry stems | Correct lean alkaline conditions | Leave it completely alone |
| Flopping in the second half of summer | No support, or shade | Net or ring the plant early next season |
Full sun, and never a damp crown
Gypsophila needs a minimum of six hours of direct sun and is visibly better on eight. In less it stretches, the stems go soft, flowering thins out badly and the plant leans towards the light in a way that no amount of staking makes look right. There is no shade tolerant way to grow it.
Just as important is what sits against the crown. Never mulch a gypsophila with compost, bark or leaf mold, and pull any that has drifted in from neighboring plants. A damp collar in autumn is the commonest cause of losing an established perennial over winter, and the plant gives no warning: it looks fine in autumn and simply fails to come up in spring.
If you want to mulch at all, use a half inch (12 mm) of coarse grit or limestone chippings spread right up to the stems. That keeps the collar dry, suppresses weeds, reflects light and warmth back into the plant, and stops rain splashing soil into the base. It is the single best thing you can do for a perennial plant's longevity.
- Clear soft mulch away from the base each autumn Pull compost, leaves and dead foliage a hand's width back from every crown before the wet season. Ten minutes of this saves more perennial gypsophila than anything else you will do all year.
- Top up the grit, not the compost Refresh the gravel collar to about half an inch deep every spring. It is doing a job, and it thins out as the plant grows through it.
- Cut off anything lying on the ground Stems bent flat by rain stay wet against the soil and rot back into the crown. Take them off at the base rather than trying to prop them up.
Water rarely and feed not at all
An established plant has a taproot going down a couple of feet and finds its own water. In a normal summer it needs none from you. Water a first year plant deeply once a week through a genuine drought and stop there; frequent light watering keeps the roots shallow and produces exactly the soft top heavy plant that flops.
A midday droop in hot weather that has gone by evening is normal and needs no action. Only a plant still limp in the cool of the morning is actually short of water. Gray, dull, slightly limp foliage that never perks up, on the other hand, is more often root rot from too much water than drought, and the two look alike for about a day before the plant dies.
Do not feed it. No general fertilizer, no liquid feed, no manure, no compost dug into the bed. Nitrogen turns gypsophila into a mound of leaf carrying a handful of flowers, and soft nitrogen fed growth is far more likely to rot at the base. If a plant genuinely looks starved on very poor sand, a single light dressing of a low nitrogen, high potassium feed in spring is the most it should ever have.
| Situation | Watering | Feeding |
|---|---|---|
| Perennial, second year onwards, in the ground | None except in extreme drought | None |
| First year plant, ground | Deep soak weekly in drought only | None |
| Annual row for cutting | Deep soak weekly in drought | None |
| In a container | When the top two inches are dry | Half strength high potassium, twice in the season at most |
| Cool wet spell, any plant | Stop completely | None |
Containers need a different mix from the border: two parts soil based compost, one part coarse grit, plus a handful of limestone chippings, in a clay pot with the drainage hole kept clear. Gypsophila in peat based compost in a plastic pot rots by midsummer.
Support the cloud before it needs it
A mature perennial makes a three foot (90 cm) dome of thin brittle stems carrying an enormous surface area of tiny flowers. Wet, that cloud weighs a surprising amount, and one summer downpour lays the whole plant flat across its neighbors. The stems kink at the base and do not stand back up.
Put a support ring or a grid of string between short stakes in place in spring, at about eighteen inches (45 cm), when the shoots are still six to nine inches (15 to 23 cm) tall. The plant grows up through it and hides it completely by flowering time. Pushing stakes in around an established plant in midsummer spears the taproot and does real damage, so this is genuinely a job that has to be done early or not at all.
Pea sticks pushed in around the crown in spring work just as well and look better, and twiggy prunings you already have are ideal. For the annual grown in rows for cutting, a single run of horizontal netting stretched over the row at a foot (30 cm) is enough, and it also keeps the stems straight, which matters if you are cutting for a vase.
Note in spring the date you put supports in and, in late summer, whether anything flopped anyway. Gypsophila that flops has almost always been fed, shaded or supported late, and one season of records tells you which of the three it was.