Fall Tree Care in Dry Weather: Tips for Homeowners

October is the pinnacle of fall weather. Foliage reaches its peak for leaf peeping, temperatures cool down, and everyone is participating in fun fall activities. October is also a vital part of a tree’s lifecycle.

Tree buds are maturing and hardening during this time, and the weather can set up or sabotage next year’s leaf and flower show. Read on to learn how weather affects tree buds, what’s considered normal for tree bud formation, what risks to watch out for, and how to prepare for October weather conditions in each region.

Bud Biology 101: Flower Buds vs. Leaf Buds 

Generally, there are two types of buds on trees: vegetative and flower buds. Vegetative buds, or leaf buds, refer to tree buds that develop into new leaves, stems, and shoots. Flower buds, as the name implies, contain the reproductive flower parts that produce fruits and flowers.

Many spring-flowering trees set buds in the summer. By October, buds reach maturity and harden, becoming more drought-tolerant and undergoing a process called lignification that provides a defense against diseases.

The onset of dormancy begins in the fall, and chill hours start to increase over time during the winter to create spring buds.

October Weather Factors That Help or Hurt

So, how does October weather affect tree buds? While it’s out of our control, knowing how weather affects tree buds can help determine what to watch out for and your next steps in care.

• Temperature Swings – In the last few years, fall temperatures have become more widely varied. Warm Octobers can delay bud hardening in trees, which makes them more vulnerable to the first hard freeze. Cool nights, on the other hand, promote lignification and help trees acclimate to chillier temperatures.
• Early Frosts & Hard Freezes – Light frosts can cue temperature acclimations, but hard freezes are more damaging. Early frost tree damage affects not-yet-hardened tissue that can kill buds and tree tips and affect spring growth in young trees.
• Soil Moisture & Drought Carryover  – Fall tree drought can affect tree bud formation. Dry soils reduce carbohydrate allocation, which can result in smaller and fewer buds. Flower buds are particularly affected by drought. Adequate moisture levels in October and November support bud viability and winter survival. 
• Wind & Desiccation – Persistent dry winds can cause desiccation, or windburn, in trees by drawing moisture from the leaves and stems faster than the roots can replace it. This can reduce growth and bud hardening. 
• Urban Heat Islands & Microclimates – Areas that are considered urban heat islands experience warmer temperatures in the fall. Warmer nights delay bud hardening, while pockets of frost increase damage risks.

Species Notes: What’s Normal for Tree Bud Formation

Much like everything else, what’s considered normal for tree bud formation depends on the species. Here are some examples of standard behavior for several species:

• Spring-flowering Ornamentals (Magnolias, Dogwoods, Crabapples) – Flower buds are typically formed earlier in this species. For these guys, October is all about hardening. Avoid pruning now or you’ll remove next year’s blooms!
• Maples, Oaks, & Zelkovas – Vegetative buds mature in October. If drought-stressed, these trees will have smaller and more sparse buds.
• Broadleaf Evergreens (Rhododendrons, Holly) – Bud scales are visible for this species in October. They need moisture in the fall to avoid winter bud kill.
• Conifers – While bud set is earlier in this species, October moisture still supports bud health.

Regional Guidance: October Tree Care

Fall doesn’t look the same nationwide. Here is a regional look at typical October weather patterns with fall tree care tips.

• Northeast (NY, NJ, CT, PA, NE) – Expect wide temperature swings and early inland frosts. Deep water your trees until the ground starts to freeze, and build a 2 to 3-inch mulch ring, avoiding volcano mulching. Avoid fertilizers high in nitrogen, and be aware of sunscald on thin-barked trees later in the season. For coastal areas, make sure to plan for salt-spray mitigation.
• Midwest (OH, MI, IL, WI, MN, IA, MO) – The freeze-thaw pattern in this region is very volatile. Summer drought carryover is a common occurrence. Test your soil’s moisture levels 6 to 8 inches deep into the ground. Deep water-stressed or young trees, avoid pruning spring-flowering species, and refresh the mulch around your trees. If you notice your tree buds are small, schedule a soil test with a plant healthcare technician.
• South (TX, GA, FL, Carolinas) – Long, warm fall seasons can cause late flushes that result in tender growth that’s vulnerable to the first freeze. Make sure to water your trees during dry spells and avoid pushing growth with high-nitrogen fertilizer. Be wary of hurricanes and soil saturation, and protect broadleaf evergreen trees from dry winds later in the season.
• Pacific Northwest – October rains aid bud hydration, but make sure to watch for proper soil drainage and root rot. Prioritize mulching and avoid waterlogging during this time.
• Intermountain, CO, & High Plains – Early freezes and low humidity call for deep watering evergreens and new plantings. Consider using an anti-desiccant later on in the season.
• Mediterranean (CA) – Dry and windy fall weather means watering is key. Make sure to maintain your irrigation cadence, add mulch, and manage wildlife ash and heat exposure during this time.

What To Do Now

With fall weather right around the corner, there are a few best practices you can do now to help make sure your trees bloom brightly come spring.

• Watering – Slow soak or deeply water your trees during dry October weeks, especially evergreens and newly planted trees.
• Mulch – Apply 2 to 3 inches of mulch, pulled back from the trunk, to stabilize moisture and temperature.
• Fertilizing – Conduct a soil test before fertilizing to ensure your soil receives the necessary nutrients. Slow-release and low-salt products work best, and potassium is helpful for hardiness if needed. Avoid over-applying nitrogen.
• Protection – Using repellents, guards and cages to protect your trees from deer and rut rubbing, which can damage buds and cambium.
• Stay Salt Free – Plan for salt protection for roadside trees.

While these precautions provide health benefits to trees, they aren’t foolproof. Contact your local certified arborist to make sure you’re getting it right.

KEEP YOUR TREES PEST-FREE THIS FALL