What to plant this week in Flagstaff, AZ
Flagstaff gardeners must keep a watchful eye on the garden as late spring frost risks linger until May, despite the calendar suggesting otherwise. This week marks the final push to harvest your Daikon radishes before the soil cools rapidly, while garlic cloves are now ready for their critical fall planting window.
The next 7 days
Flagstaff, AZGrowing in Flagstaff right now
- Soil temperatures in Flagstaff's high desert plateau remain chilly; wait at least two weeks after the last frost date (May 15) before transplanting any cool-season crops to ensure survival.
- The city's thin, rocky soil drains quickly but dries out fast under intense afternoon sun; mulch heavily around transplants to retain moisture and moderate root zone temperatures.
- Spring snowpack melt can create sudden micro-floods in lower wash areas; check drainage before planting seedlings in low-lying zones near the San Francisco Peaks.
Sow this week
No direct sowing windows open this week.
Transplant this week
Nothing is due to go out this week.
Harvest soon
2 crops- Daikon Radish
- Garlic
Seasonal tips
- Apply fresh mulch now to retain soil moisture as temperatures rise.
- Test soil pH before adding any compost or amendments for new transplants.
- Keep a close eye on emerging seedlings to protect them from late spring fluctuations.
Pest & disease watch
- Spider mites are becoming active on hostas and ornamentals as humidity drops, causing stippling damage that looks like dirt spots on leaves.
- Aphids often colonize new garlic sprouts in early spring; monitor closely and rinse with a strong water jet or apply neem oil before they establish.
Watering this week
Water deeply but less frequently now that the soil is warming up, encouraging strong root development.
Harvest Daikon Radish promptly before the heat sets in to ensure the best crunch and flavor.
Flagstaff gardening questions
3Can I plant lettuce seeds outdoors now in Flagstaff?
No, you should wait until mid-May after the frost danger passes completely. Starting seeds indoors is safer now so they are hardened off by the time temperatures stabilize.
When exactly should I plant my garlic for next year's harvest?
Plant your garlic cloves immediately this week while the soil is still cool but workable. Aim to get them in by early November for a strong spring bulb formation.
My Daikon radishes are growing fast, when do they peak?
Harvest your Daikon radishes now before the ground freezes hard or if you see them swelling past their ideal size. They store well in the cool Flagstaff winter if dug up and cured properly.
Other cities in zone 6a
12See the full zone 6a guide → · Plan your Flagstaff garden in SproutGuide →