Seasonal Guide

Idaho Yard Maintenance Calendar — Month by Month

Every yard task organized by month for Eastern Idaho. Never miss a critical maintenance window — from January planning through December prep.

January

Winter

Winter

+Start seeds indoors under grow lights (tomatoes, peppers, flowers) 6-8 weeks before last frost
+Prune dormant fruit trees on a mild day (above 20°F) — before sap begins to flow
+Inspect fence posts for frost heave damage — note any that have shifted or leaned
+Plan irrigation changes — now is the time to redesign sprinkler zones before spring startup
+Order sod, plants, and materials for spring projects — popular items sell out by May

Early Spring

+Prune deciduous trees and shrubs before bud break — remove dead, damaged, and crossing branches
+Rake lawn to remove dead grass, leaves, and debris (light raking, not aggressive dethatching)
+Inspect fence line after winter — check for leaning posts, broken panels, and loose hardware
+Clean up perennial beds — cut back last year's growth on ornamental grasses, sedum, and perennials
+Check retaining walls and hardscaping for frost heave damage — note any shifting or cracking

Spring

+Apply pre-emergent crabgrass preventer when soil temperature reaches 55°F (usually mid-April)
+Apply first lawn fertilizer (slow-release, high nitrogen) in late April
+Turn on sprinkler system after last hard freeze risk — test all zones for broken heads and leaks
+Begin mowing when grass reaches 3.5-4 inches — set mower at 3 inches
+Spot-treat broadleaf weeds (dandelions, clover) as they emerge — liquid spray is most effective

Spring

+Peak planting season — install trees, shrubs, perennials, and annuals after May 15 frost date
+Install sod — the spring window is May 15 through June 30
+Start fence and hardscaping projects — contractors are booking up fast
+Mow weekly at 3-3.5 inches — grass is growing rapidly
+Mulch planting beds — 3-4 inches of rock or bark mulch for weed suppression and moisture retention

Early Summer

+Apply second lawn fertilizer (slow-release, balanced formula) in early June
+Increase irrigation to 1-1.5 inches per week as temperatures rise
+Deadhead spent flowers on perennials and annuals to encourage continued blooming
+Watch for insect damage — white grubs, aphids, and spider mites are common in Idaho
+Complete any remaining planting — mid-June is the cutoff for most transplanting until fall

Summer

+Water is priority #1 — maintain 1-1.5 inches per week, water early morning (5-8 AM)
+Raise mower height to 3.5-4 inches — taller grass handles heat better
+Do NOT fertilize — July heat plus fertilizer can burn the lawn
+Harvest vegetables regularly — pick squash, beans, and tomatoes to encourage continued production
+Inspect and tighten fence hardware — summer heat can expand and loosen fasteners

Summer

+Continue watering deeply — August is often the hottest and driest month in Eastern Idaho
+Plan and book September aeration and overseeding service NOW — schedules fill fast
+Take notes on what performed well and what struggled — use this for fall planting decisions
+Begin preparing beds for fall planting — remove spent annuals and amend soil with compost
+If lawn went dormant (brown), let it rest — it will recover with cooler temps and fall rain

Fall

+AERATE the lawn — the most important lawn care task of the year in Idaho
+OVERSEED bare spots immediately after aeration — September is the best seeding window
+Apply fall fertilizer (most important application of the year) — high nitrogen, slow-release
+Plant trees, shrubs, and spring-blooming bulbs (tulips, daffodils, crocus)
+Begin reducing mowing height gradually to 2.5-3 inches through the month

Fall

+Winterize sprinkler system by October 15 — blow out all lines to prevent freeze damage
+Apply winterizer fertilizer (high potassium) in mid-October
+Final mow at 2.5 inches — slightly shorter going into winter reduces snow mold risk
+Rake leaves promptly — thick leaf layers smother grass and promote disease
+Plant garlic cloves for next year's harvest — October is ideal in Idaho

Late Fall

+Final leaf cleanup — remove all leaves from lawn and beds before first snow
+Protect young trees with tree wrap to prevent sunscald from winter sun-and-shade cycles
+Drain and store garden hoses — frozen hoses crack and split
+Store outdoor furniture or cover with weatherproof tarps
+Avoid walking on frozen grass — it damages crowns and creates dead spots in spring

Winter

+Plan next year's projects — use winter downtime to research, get quotes, and set budgets
+Avoid piling snow from shoveling directly against fence posts — snow weight can push posts over
+Check for rabbit and rodent damage on young tree trunks — use hardware cloth guards if needed
+Keep holiday decoration stakes and lights off the lawn as much as possible — they compact soil
+Gift yourself new garden tools — winter sales offer the best prices on quality equipment