On this page:
Highland Frost Dates & Growing Season
Here's the frost forecast for the next three days (last updated on December 8th, 2025 6:08 AM).
Dec 8th
False Security / Chilling Injury (Too cold for Basil)
Dec 9th
False Security / Chilling Injury (Too cold for Basil)
Dec 10th
Safe
Warning: The soil temperature is forecasted to drop to 1.3°C tonight. We recommend covering seedlings, tender perennials, and low-lying crops with horticultural fleece or cloches to prevent damage.
Last Frost Date (Spring)
The average last frost date for Highland is May 15th. We recommend waiting until May 29th before planting tender crops outdoors.
First Frost Date (Autumn)
The average first frost date for Highland is October 20th.
Growing Season
Based on historical data, the growing season in Highland is approximately 158 days long.
Highland Planting Calendar
This weekly planting calendar displays the ideal windows for starting seeds, transplanting, and harvesting.
Highland Monthly Gardening Guide
March
In March, you can start Cabbage indoors, start Aubergine indoors, start Lavender indoors, start Begonia indoors, and start Coneflower indoors.
April
In April, you can start Cantaloupe indoors, sow Chervil outside, sow Lettuce outside, sow California Poppy outside, and sow Garden Cress outside.
May
In May, you can sow Beet outside, sow Butternut Squash outside, sow Swiss Chard outside, sow Fenugreek outside, and sow Moss Rose outside.