Bald cypress

Taxodium distichum

also called swamp cypress, taxodium

The tree of southern swamps that turns out to thrive on dry city streets: feathery soft needles, a neat pyramid, rust-orange fall color, and then bare winter bones, because this conifer sheds.

Light Full sun
Water Anything; it defines flood-tolerant and shrugs at drought once rooted
Hardiness Hardy
USDA zones 4b–11a
Height 15–25 m
Spread 29 ft 6 in
Spacing 7–10 m
Sow depth From a young tree
Root depth 12–24 in
Type
Tree · Perennial
Botanical family
Mixed / other
Foliage color
Green
Sunlight
Full sun
Watering
Anything; it defines flood-tolerant and shrugs at drought once rooted
Soil
Anything from standing swamp water to a dry parking-lot strip
Feeding
All-purpose balanced
USDA zones
4b–11a
Frost tolerant
Yes
Plant out
14 days before the last spring frost
Plant spacing
26 ft 3 in
In-row spacing
19 ft 8 in
Between rows
32 ft 10 in
Square-foot density
Not suited to SFG
Root system
Woody, shallow and far-reaching
Working depth
12–24 in
Can reach
4 ft down where the soil allows
Spread
59–89 ft across, about 2–3× the width of the plant

Almost all of a tree’s roots are in the top two feet of soil, where the air is, and they run out well past the branch tips. The deep taproot most people picture belongs to the seedling; the tree grows out of it and spends the rest of its life spreading sideways instead.

In wet ground it sends up woody "knees" from the roots, several metres out from the trunk, which is charming beside a pond and awkward in a lawn. On ordinary garden soil it usually makes none at all.

The habit is Bald cypress’s own; the figures are what that habit usually comes to at this size, not a measurement of this species. Roots follow the soil either way: a compacted pan, a high water table or heavy clay stops them well short of any of it, and deep open ground lets them go further.

When
Not harvested. A winter bagworm check is the one recurring job.
What to look for
Spindle-shaped bags hanging like small brown cones among the real ones in the bare winter crown.
How to harvest
Hand-pick and bin every bag you can reach before the eggs hatch in late spring. Prune only deadwood; the pyramid shapes itself.
How often
One winter look. And once in November, resist the urge to declare the rusty, needle-dropping tree dead: it does this every year.
Storing the crop
Nothing to store. The fallen needles are a fine soft mulch exactly where they land.

Beneficial predators that hunt this plant's pests — grow their favourite flowers nearby to recruit them. companion plant

  • Garden birds Passeriformes
    Hunts Bagworms

    Both things are true: birds strip your currants and a brood of blue tits takes several thousand caterpillars out of one fruit tree in a fortnight. Net what you must and welcome them everywhere else — a nest box near the apples is worth more than a spray.

  • Minute pirate bug Orius spp.

    A pinhead-sized true bug that is the best natural check on thrips, and happily spears aphids, mites, and insect eggs too. It needs pollen when prey is scarce, so keep something flowering nearby.

  • Parasitic wasps Braconidae & Trichogramma
    Hunts Bagworms

    Tiny, stingless wasps that lay eggs in or on caterpillars, aphids, and moth eggs — the white cocoons riding a hornworm are their calling card, so leave that caterpillar be. Umbel flowers with shallow nectar keep the adults fuelled.

  • Predatory mites Phytoseiulus & Amblyseius

    Fast orange mites that hunt spider mites egg-by-egg, and cousins that clear thrips and fungus-gnat larvae. Sold as a biological control for greenhouses; outdoors they follow humidity — mist and mulch, don’t dust with sulfur.

The famous "knees" rise only where roots sit in water or a soggy lawn; on ordinary ground it makes none. Individual trees in the Carolinas have passed 2,600 years, the oldest known trees in eastern North America.