What to plant this week in Tucson, AZ
With the last frost in Tucson historically wrapping up by late January, this week marks a critical mid-season push for your summer crops as temperatures stabilize above 75°F. While you cannot transplant anything new right now due to heat stress risks, it is an ideal time to sow warm-weather staples like bush beans and cantaloupe that will mature before the intense July heat hits. Focus heavily on harvesting your maturing melons, corn, and squash, as these plants are nearing peak production in our dry desert climate.
The next 7 days
Tucson, AZGrowing in Tucson right now
- Our hardpan clay soil requires frequent deep watering to encourage roots to bypass the surface crust; avoid light sprinklers that merely wet the top inch.
- Mulch heavily around the base of your okra and watermelon with straw or wood chips to reflect heat and retain moisture in this arid environment.
- Apply a slow-release nitrogen fertilizer now to support rapid growth on newly sown bush beans before the mid-summer drought stress sets in.
- Monitor soil pH periodically; our native alkali soils can lock up nutrients, so ensure you are testing for magnesium and calcium deficiencies.
Sow this week
26 crops- Basil
- Borage
- Bush Bean
- Cantaloupe
- Cleome (Spider Flower)
- Cosmos
- Cowpea (Black-Eyed Pea)
- Cucumber
- Edamame
- Fennel
- French Marigold
- Garden Verbena
- Lima Bean
- Malabar Spinach
- Nasturtium
- Okra
- Pole Bean
- Scarlet Runner Bean
- Shiso (Japanese Basil)
- Summer Savory
- Sweet Corn
- Thai Basil
- Vinca (Madagascar Periwinkle)
- Yellow Summer Squash
- Zinnia
- Zucchini
Transplant this week
Nothing is due to go out this week.
Harvest soon
36 crops- Basil
- Borage
- Bush Bean
- Cantaloupe
- Cleome (Spider Flower)
- Cosmos
- Cowpea (Black-Eyed Pea)
- Cucumber
- Edamame
- Fennel
- Flour Corn
- French Marigold
- Garden Verbena
- Garlic
- Gourd (Ornamental/Bottle)
- Honeydew Melon
- Lima Bean
- Loofah (Luffa)
- Malabar Spinach
- Nasturtium
- Okra
- Pole Bean
- Pumpkin
- Roselle (Cranberry Hibiscus)
- Scarlet Runner Bean
- Shiso (Japanese Basil)
- Summer Savory
- Sunflower
- Sweet Corn
- Thai Basil
- Vinca (Madagascar Periwinkle)
- Watermelon
- Winter Squash
- Yellow Summer Squash
- Zinnia
- Zucchini
Seasonal tips
- Sow heat-loving seeds directly into warm soil after the last frost date passes.
- Thin out dense seedlings like beans and corn to ensure proper air circulation.
- Apply a light layer of mulch around established plants to retain moisture as temperatures rise.
Pest & disease watch
- Spider mites are exploding in population as humidity drops and temperatures climb above 90°F, particularly on the undersides of zinnias and marigolds.
- Aphids frequently colonize the new growth of sweet corn and pole beans during this dry season, requiring early intervention with water sprays or insecticidal soap.
- Cactus bugs may appear sporadically from dormant desert plants, but check for their black, tar-like droppings on your squash vines as a sign of infestation.
Watering this week
Provide deep, consistent watering at the soil line to encourage strong root development in these heat-loving annuals.
Succession sow bush beans every two weeks throughout this spring window to ensure a continuous harvest all summer long.
Tucson gardening questions
3Can I plant any cool-season crops now in Tucson's zone 9b heat?
No new transplants are recommended this week because the soil is too hot and dry to shock seedlings without significant shade and mulching. Stick to sowing only warm-weather varieties like basil, okra, or cucumbers listed for immediate planting.
My cantaloupes look ready but haven't fallen yet; how do I know when to pick them?
In our dry climate, wait until the stem near the fruit turns brown and the melon sounds hollow when tapped with your knuckles rather than dull. Do not rely on color alone, as the skin may remain green even at full maturity in Tucson sun.
How often should I water my summer squash to prevent blossom end rot?
Water deeply every 2-3 days depending on evaporation rates, ensuring moisture reaches below the hardpan layer where roots drink. Inconsistent watering is the primary cause of blossom end rot, so avoid letting the soil dry out completely between irrigations.
Other cities in zone 9b
10See the full zone 9b guide → · Plan your Tucson garden in SproutGuide →