Beet armyworm in Hawaii: When It Shows Up and What Stops It
Beet armyworm shows up in Hawaii year-round, not on a seasonal schedule like it does on the mainland.
Gardening in Hawaii
Everything we have worked out for Hawaii: what to plant and when, which varieties finish in time, the pests that actually turn up here, and the jobs that pay off month by month. We also cover the rest of the property, from lawns and soil to home care and energy, because a garden rarely stops at the vegetable bed.
The numbers first, because everything else follows from them. Measured at the weather station in Honolulu, the last spring freeze falls around no freeze occurs in inhabited areas and the first fall freeze falls around no freeze occurs in inhabited areas, USDA zones 9a-13a, 9,934 growing degree days in the year.
Heat, not frost, is what shortens the season here: above 86 °F tomato pollen goes sterile, so growers run a spring crop and an autumn one rather than a single long season. Garlic is the awkward one: only 0 weeks below 40 °F, where it needs six to split into cloves. Chill the cloves before planting, or grow a softneck type.
Elsewhere on the property in Hawaii: the pests that turn up here.
Figures from NOAA's 1991-2020 climate normals. A state is not one climate: elevation, a large lake or the coast can move these dates by two weeks either way, so check your own county with the extension service before you spend money.
Cabbage webworm in Hawaii: When It Shows Up and What Stops It
Cabbage webworm (Hellula undalis) turns up wherever crucifer crops are growing in Hawaii, essentially all year, because the islands never get cold enough…
Trees, Shrubs and Perennials for Hawaii: What Will Not Survive
Hawaii’s hardiness range runs from USDA zone 9a to zone 13a, according to the USDA Plant Hardiness Zone Map.
How Much Insulation Does a Home in Hawaii Need?
Hawaii sits entirely in IECC climate zone 1A, the mildest zone the code recognizes, and every island shares it.
When Can You Turn the Heat Off in Hawaii?
In Hawaii, there is no month you switch the heat off, because there is essentially no heating season to switch off from.
Will Sweet Corn Ripen in Hawaii?
Yes, sweet corn ripens in lowland Hawaii, but not because of a spring-to-fall frost calendar. There isn’t one.
When to Sow Sweet Corn in Hawaii
There’s no frost calendar to consult here, so the question really comes down to soil temperature and elevation.
When to Sow Autumn Spinach in Hawaii
Autumn spinach in Hawaii goes into the ground once soil temperature drops out of the germination danger zone, not on a date pulled from a frost calendar.
Will Spinach Bolt Early in Hawaii?
In lowland Hawaii, spinach bolts early almost every time it’s grown outside the coolest stretch of the year.
Will Hawaii Soil Hold an Asparagus Bed for Fifteen Years?
Yes, mostly. The Hilo series, the soil USDA lists as representative of Hawaii, is a well-drained volcanic-ash Andisol, and “well drained” is the only…