Watering new plants is one of the most critical steps during the first 90 days of planting. If done correctly, it encourages strong root growth and deep rooting, setting your plants up for long-term health. Whereas if done poorly, it can lead to stress, weak root systems, or even rot. In this guide, we’ll walk you through how much water to apply, when to water, and how to deliver water to the base of the plant for the best results.
Establishing Your Plants: Timing and Technique
Deep watering twice a week during the first 90 days or until December 1 is essential to encourage roots to grow deep into the soil. These sessions prime the root system to tap into deeper moisture rather than staying near the surface.
Use the 5 - 15 - 30 second rule to guide your amount of water per plant:
- Perennials and small shrubs: Water for 5–15 seconds each.
- Medium shrubs: 15–30 seconds.
- Trees and large shrubs: 30 seconds or more.
This ensures you deliver water directly to where plants roots are developing.
Is It Time to Water? Checking Soil Moisture
Before each watering, test the soil. Dig 3–4 inches down near the root zone; if the soil is dry, it’s time to water. Simply relying on surface dryness can be misleading—a dry top inch may hide moist soil below. Keep the soil damp but not soggy to avoid root rot.
Weather conditions matter too: on hot or windy days, moisture evaporates faster, so you may need to adjust your schedule accordingly.
Delivering Water: Drip, Soaker, or Sprinkler?
When choosing an irrigation system, go for precision:
- Drip irrigation systems deliver water directly at the base of the plant, targeting the root zone and minimizing evaporation.
- Soaker hoses also release water slowly along their length—effective for beds with evenly spaced plants.
- Sprinkler systems are better suited for watering lawns and wider turf areas, but they spray overhead and often wet foliage unnecessarily.
For new plantings, drip and soaker systems are preferred—they focus water at the roots, encouraging strong absorption and root growth.
How Much & How Often to Water
A good rule of thumb is to supply around an inch of water per week—split into two deep watering sessions following the timing rule above. This promotes deep rooting and minimizes frequent surface watering.
If you’re also watering lawns nearby, note that for sod and seeded lawns, watering may need to be light and frequent: 1–3 times daily during the first month, transitioning to 1–2 heavier sessions per week.
Balance is key: if your lawn sprinkler overlaps planting beds, be mindful not to overhydrate your young trees and shrubs.
Focus on Roots: Water at the Plant Base
Always water at the base of the plant, not the foliage. This ensures water only reaches the root system, where it’s absorbed most effectively. Wetting leaves can encourage disease and waste precious moisture through evaporation. Concentrating your water at soil level lets it soak in directly to where plants roots can absorb it efficiently.
Deep watering supports the development of deep rooting, making plants more resilient to dry spells. Plants with shallow watering habits remain near the surface, requiring more frequent watering and being more vulnerable to drought. A well-established root system will help plants thrive even in challenging weather.
Monitor & Adjust as Roots Develop
Continue monitoring soil moisture and plant health. Look for signs such as wilting or yellowing leaves, which may signal overwatering or underwatering. As root growth progresses, you can gradually dial back frequency and increase soak depths. Use your irrigation system controls or manual watering schedule accordingly.
If you’re maintaining both turf and new plantings, keep irrigation routines separate. Use the sprinkler system for lawns and drip or soaker hoses for ornamentals, trees, and shrubs. This keeps the amount of water optimal for each zone, avoiding runoff and conflicting needs.
Actionable Checklist
- Deep water twice weekly during the first 90 days, following the 5‟-‟15‟-‟30 second rule.
- Always check soil moisture 3–4 inches deep before watering.
- Use drip irrigation systems or soaker hoses to deliver water at the base of the plant.
- Aim for about an inch of water weekly per planting zone.
- Water early in the morning to reduce evaporation; adjust for weather conditions.
- Focus water at soil level to maximize absorption by plants roots and support root system development.
- Monitor foliage and soil—adjust schedule as root growth expands.
- Keep lawn watering separate from planting irrigation.
Proper watering of new plants—delivering the right amount of water deep to the roots, using targeted irrigation systems, and adapting for weather conditions—makes all the difference in building a strong, resilient root system. Follow these guidelines consistently through the critical establishment phase, and you’ll be rewarded with thriving trees, shrubs, flowers—and a garden that grows with confidence.
