Every November we get the same worried message: “My redwood has gone brown and is dropping its needles. Is it dead?” Nine times out of ten, the answer is no. Redwoods change through the seasons, and some of those changes can look alarming if you’re not expecting them.
The Dawn Redwood (Metasequoia glyptostroboides) is one of the few deciduous conifers. Each autumn its soft green needles turn a rich rusty orange, then fall, often still attached to the small side shoots they grew on. By December the tree can look completely bare.
This is exactly what it should do. In spring, fresh bright green needles appear again from buds along the branches.
To check it’s alive:
Look for small, plump buds along the stems.
Gently scratch a thin twig with your fingernail. Green underneath means it’s alive.
Bend a young shoot. It should flex, not snap.
Evergreen Coast Redwoods (Sequoia sempervirens) also shed some foliage. Older needles on the inside of the tree turn brown and drop each year, while the outer growth stays green. That’s normal housekeeping.
In cold weather, many Coast Redwoods take on a bronze, purple or reddish tinge. This is a natural response to frost and cold wind, and the green colour returns as temperatures rise in spring.
Giant Redwoods (Sequoiadendron giganteum) keep their blue-green, scale-like foliage all year, but old inner sprays brown and fall over time. If the outer growth and the leading shoot look healthy, there’s nothing to worry about.
Browning is more likely to be a problem if:
New growth at the tips is turning brown, not just inner or older foliage.
A whole evergreen tree browns quickly.
Shoots are dry and brittle and snap when bent.
The compost in a pot is bone dry, or sitting waterlogged.
Most problems in young trees come down to water: too little in summer, or roots sitting in wet compost in winter. If you’re unsure, send us a photo and we’ll happily take a look.
This is the first in a short winter series. Next week we’ll look at planting a redwood this winter, followed by winter protection, Christmas gift ideas and growing redwoods from seed.
Thinking of adding autumn colour to your garden? Take a look at our redwood trees for sale.