Arizona Garden in April

By: Angela Judd | April 4, 2025

This is a Growing in the Garden FREE Printable.

April is a pivotal month in the Arizona garden, with warm days and cool nights providing ideal conditions for growth. However, with rising temperatures ahead, now is the time to complete key gardening tasks to set up for a successful season. This guide covers everything you need to do in an Arizona garden in April, including vegetable and herb care, flower and rose maintenance, fruit tree pruning, container gardening, landscape upkeep, watering strategies, and pest control.

The low desert of Arizona includes areas below 3,500 feet in elevation, such as the Phoenix and Tucson metro regions. Gardening in these regions comes with unique challenges, but by taking the right steps now, your garden will be better prepared for the heat ahead.

Whether you’re thinning fruit, fertilizing plants, or refreshing garden beds, taking action now will help your Arizona garden in April thrive. For a month-by-month guide to keeping your garden productive all year, visit my Arizona Monthly Garden Guides.

Looking for what to plant this month? Check out my companion post, What to Plant in April.

Click on the title to jump to that section and learn more about what to do during April:

April YouTube Videos
Vegetable Gardening Tasks for April
My April Garden Journals
Garden Pests in April
Container Gardening Tasks
Flower Gardening Tasks
Caring for Roses During April
Herb Gardening
Fruit Trees, Berries, and Citrus
Landscape Plant Tasks During April
Watering Your Garden and Landscape

April YouTube Videos

Vegetable Gardening Tasks for April

Clear out remaining cool-season vegetables to make space for upcoming warm-season crops.

Prepare garden beds by pulling back the mulch and adding a thick layer of compost on top of your soil. Add a generous sprinkle of worm castings. Water in well.

For more soil-building tips, visit my guide: How to Prepare Your Soil for Planting.
Want to enhance your garden beds even more? Check out my Composting with Worms Guide to learn about in-bed worm bins.

Thin seedlings and transplants. Give each plant enough room to grow.

Fertilize strawberries, onions and garlic this month. I recommend this fertilizer—great for strong growth.

Feed newly planted grapes in April. I recommend this fertilizer for grapes. (Established grapes should be fertilized in February and May.)

Provide support for tomatoes. Proper support will encourage strong plants and higher yields. I just started using these tomato cages from Garden in Minutes, and they are awesome. It is designed to fit within the watering grids and is super tall, so even indeterminate tomatoes have enough support.

Watch out for blossom end rot, especially on the first tomatoes of the season. Prevent it by watering evenly and consistently.

For more tips on handling blossom end rot, check out my Blossom End Rot Guide.

Hand-pollinate early squash blossoms in the morning. The first squash fruits often need help setting fruit. Gently transfer pollen from male to female flowers (the ones with a tiny squash at the base) remove the male blossom or use a small paintbrush or cotton swab.

Install shade cloth when temperatures consistently reach above 90°F (32°C). This can cool the air by about 10 degrees and give you more time for crops to produce before it gets hot.

Need more details? Here’s my Shade Cloth Guide.

Add a thick layer of mulch (about 3-4 inches) around your vegetables to keep moisture in and soil temperatures stable.

Read my Mulching Guide for extra tips and benefits of adding mulch to your Arizona garden in April.

Get my April Garden Journals in GITG Academy

Twice a month, I send my personal garden journal to members of “Growing in the Garden Academy.” From the first seedling to the last harvest, you can follow my gardening adventures in Arizona’s unique low desert. Access the past three years of garden journals and monthly classes as a member.

Learn more about GITG Academy & Low Desert Tips

Garden Pests in April

Aphids
Aphids are especially active this month. I prefer letting beneficial insects—like ladybugs and lacewings—take care of the problem rather than stepping in right away. Encouraging helpful bugs by allowing cilantro and dill to bolt (flower) and planting nectar-rich flowers such as alyssum goes a long way in keeping aphids under control. Learn more ways to attract beneficial insects in this guide.

Alyssum can also act as a valuable companion plant. Learn how to grow alyssum in this guide.

Ladybugs are a gardener’s best friend against aphids. Learn to recognize every stage of their life cycle—from larva to adult—so you can protect them and let them work their magic in your garden! Learn more in this guide.

Potato Bugs (Roly-Polies)
These curious little crustaceans can become a nuisance in spring. For tips on managing them organically, check out my Potato Bug Management Post.

Genista Broom Moth Larvae
You might spot these on Texas Mountain Laurel. Some leaf damage is normal and usually doesn’t harm the plant long-term. If the infestation becomes severe, you can use Bacillus thuringiensis (Bt) to help control them.

Container Gardening Tasks

Wrap Up Small Containers
As small containers finish producing, I often repurpose their soil by adding it to my garden beds, using it as mulch around trees, or mixing it into my compost. Then, I clean and store those small containers until cooler weather returns.
Keep Growing in Large Containers
Containers of 20 gallons or more can withstand Arizona’s intense summer heat more effectively. If you plan on planting summer crops in these larger containers, refresh the potting mix first. Learn how in my Potting Soil Refresh Guide.

A Note About Oyas in Containers

Oyas are small, porous clay pots you bury in the soil. They release water slowly as the soil dries, providing steady moisture right where roots need it. This reduces how often you need to water and helps plants survive hot, dry weather.

Click here to purchase Oyas and see if they’re right for your container garden.

Flower Gardening Tasks

Collect Seeds
Harvest seeds from spring wildflowers and other cool-season annuals you sowed in October and November. Save and reseed your favorites next season!

For more tips on wildflowers, check out my Wildflower Guide.

Wildflowers in my Arizona Garden in April

Once winter-growing flowers and other annuals have finished blooming, remove them. Keeping worn-out plants invites pests, so clearing them out helps maintain a healthier garden.
Give young summer flowers enough space to grow by thinning out any overcrowded seedlings.
Pinch back basil, zinnias, dahlias & marigolds to encourage branching.
Arizona’s heat arrives fast, so skip planting new cool-season annuals this month. Their window to thrive is simply too short. Focus instead on warm-season blooms.

Need ideas? Check out my Favorite Heat-Loving Flowers for blooms that can handle our intense summer days.

Plant Sunflowers
Sunflowers can be planted through July. They can provide welcome afternoon shade. I like planting them on the west side of my garden beds to help shield other plants from the hottest sun. For more details, visit my How to Grow Sunflowers Guide.

The Perpetual Annual Flower Planting Calendar, available in my shop, helps you learn when to plant flowers in the low desert of Arizona and whether to plant seeds or transplants.

Caring for Roses During April

April is a beautiful month for roses—often, their peak bloom in the low desert.

Fertilizing:
- Established Roses: To encourage continual blooming, consider using a water-soluble fertilizer twice this month rather than a single application of granular fertilizer. This steady supply of nutrients encourages abundant blooms.
- New Roses (in the ground less than one year): Always use a water-soluble fertilizer only. This gentler approach helps new plants establish strong, healthy root systems without burning the roots.
Own-Root Roses: I love planting own-root roses from Heirloom Roses in my garden. You can see my favorites here. Use code GROWINGAZ20 to save all year long.

For more detailed tips on rose care for your Arizona garden in April, check out my Rose Growing Guide.

Herb Gardening

Let dill bloom! Its flowers attract pollinators and beneficial insects, making it a great companion for many vegetables. Learn more in my How to Grow Dill guide.
Once it flowers, collect the seeds (known as coriander) to replant or use in your kitchen. Need details? Check out my How to Grow Cilantro post.
Hold off on pruning woody herbs like lavender, rosemary, sage, or thyme until fall. It’s fine to trim summer herbs—basil, lemongrass, and mint—this time of year.
Consider planting basil beside each tomato plant. The bees—and your tomatoes—will thank you. Learn more in my How to Grow Basil guide.
Keep basil pinched back to encourage branching until plants grow large and bushy.

For more tips on pairing herbs with summer vegetables, see my Warm-Season Companion Plant Guide. And if you’re looking for ways to keep herbs thriving year-round, don’t miss my How to Grow Herbs in a Hot Climate guide.

Fruit Trees, Berries, and Citrus

Check Tree Tags
Trees grow quickly and can outgrow their tags, which might girdle branches if left unattended. Move or reattach tags to smaller branches.
- Learn more about how to label trees in my Labeling Guide.
Wrap Citrus Bark
Newly exposed bark is vulnerable to sunburn. Use tree wrap or a 50/50 mix of water-based paint and water. Avoid over-pruning—lower branches help shade the trunk.

Light Citrus Pruning
Remove dead, damaged, or crossing branches, and watch for water sprouts on lemon trees. See my Guide to Citrus Suckers and Sprouts for details.
Thin Fruit on Deciduous Trees
Thin fruit before it’s about an inch in diameter (usually within a month of full bloom). Leave 4–6 inches between fruit.
- More details in my Guide to Thinning Fruit Trees.
Fertilizing & Feeding
- Blackberries and Deciduous Fruit Trees: After bud break, feed with a fruit tree fertilizer or apply compost or worm castings. (See my Organic Fruit Tree Feeding Guide.)
- Water Thoroughly: Always water deeply before and after fertilizing.
Harvesting
- Grapefruit (Rio Red): Harvest from December through summer. Juice extras—my Citrus Juicing Tips can help.
- Early Peaches (Earligrande): Might be ready now—pick before birds do! See my Peach Tree Guide.
Train or Prune
- Pomegranates: Prune to a manageable size or train against a wall. Growing Pomegranate Guide.
- Grapevines: Prune before they leaf out. Growing Grapes Guide.

By thinning, fertilizing, and pruning your fruit trees and citrus properly this month, you’ll set them up for a strong growing season and abundant harvest!

Landscape Plant Tasks During April

Clean Up & Refresh

Remove any dead or struggling plants. Scratch the bark to check for green tissue (life) before deciding to replace.
Apply a 2–3 inch layer of mulch around shrubs and trees to keep soil cooler.

Prune

Cut out dead or damaged branches for better airflow.
Prune spring-flowering shrubs after they finish blooming; water well afterward.
Trim frost-damaged plants like hibiscus and lantana.
Avoid pruning or fertilizing newly planted trees and shrubs—let them settle in.

Weed Control

Pull weeds before they go to seed.
Remove stinknet (an invasive weed) promptly, and bag it—don’t compost.

Planting

April is great for most trees, shrubs, and perennials, including frost-tender varieties.
Give new plants enough space to grow.
Plant early to help them establish before the heat arrives.

Fertilizing

Fertilize only established trees and shrubs if needed. Native plants often don’t require extra feeding.
Consider using Nutrient +, compost or worm castings for an organic boost.
Skip fertilizing new plantings until they’re established.

Boost plant recovery with Nutrient+ from Arizona Worm Farm

Watering Your Garden and Landscape

Check Your Irrigation System
Run your system, look for leaks, and ensure proper coverage.

I use Garden Grids from Garden in Minutes in my raised beds for even watering and easy adjustment. Use code Angela10 to save $10 off $100, or GITG5 to save 5% on any size order.

Deep Water Landscape Plants
Give established shrubs and trees a thorough soaking to flush out salts and prepare for summer’s heat.

Watering Frequency

Annuals: Water to about 12 inches deep, then let the top inch of soil dry before watering again.
Containers: Check moisture with a meter or by feeling the soil; they dry out faster than in-ground beds.
Citrus Trees: Water established trees every 2–3 weeks.
Fruit Trees: Water established trees once every 7–10 days.

Conserve & Plan
For guidelines on efficient watering, visit WaterUseItWisely.com or check out my Watering and Water Conservation Resources. Consistent, deep watering now sets the stage for strong, resilient plants all summer long.