Raintree Growing Guide
Almond Trees
One of the world's most beloved tree nuts — and one of the most climate-specific. When matched to the right site, almonds reward home growers with heavy harvests of sweet, rich kernels that no grocery store can match for freshness and flavor.
AT A GLANCE
SUN
8+ hours of direct sunlight in early summer; full sun required for good nut production
USDA ZONES
Zones 5/6–9 depending on variety; most standard sweet almonds perform best in Zones 7–9
SOIL PH
6.0–7.5; optimal 6.3–6.8 on Lovell rootstock, 6.8–7.2 on Marianna plum rootstock
POLLINATION
Most varieties require cross-pollination with a second compatible almond variety; some are self-fertile
Chill Hours
200–500 hours depending on variety; one of the lower-chill nut crops
Growing difficulty
Very Difficult — needs hot dry summers; not suited to maritime PNW
First Harvest
3–4 years after planting; full production by year 5–6
Mature Size
15–20 ft on Lovell rootstock; 12–15 ft on Marianna 2624 plum rootstock
Harvest
October in the Pacific Northwest; late summer–fall elsewhere when hulls split open
Why grow almonds?
Almonds (Prunus dulcis, syn. Prunus amygdalus) are one of the most historically important tree nuts in the world — native to Iran and Central Asia, cultivated for millennia across the Mediterranean, and now grown on every continent where the climate cooperates. What makes the home-grown almond exceptional is timing: tree-ripened nuts harvested at peak are dramatically richer and more complex than the commercially processed nuts sold in bulk.
The sweet almond is what most home growers are after — the kernel inside the pit is eaten raw, roasted, or pressed for oil, and its flavor at true ripeness is buttery, fragrant, and complex. Bitter almonds (P. dulcis var. amara) are a distinct type; their kernels contain amygdalin (which converts to cyanide) and must be cooked or processed before consumption. Bitter almond oil is used for almond extract. Raintree carries sweet almond varieties only.
Climate match is everything. Almonds bloom very early in spring — sometimes as soon as late February in milder locations — and that early bloom is both the tree's greatest strength and its greatest vulnerability. A properly sited almond in the right zone is a long-lived, productive, relatively low-maintenance tree. An almond planted where late frosts are common, or where summers are too cool for hull split, will be a persistent disappointment. Read the climate section carefully before selecting a planting site.
Climate requirements
Almonds have a specific and non-negotiable climate profile. They need mild, wet winters (for chill accumulation), dry springs (for bloom and pollination), long hot dry summers (for kernel development and hull split), and relatively frost-free conditions during and after bloom.
Hardiness zones
Most standard sweet almond varieties perform best in USDA Zones 7–9. A handful of cold-hardy varieties — notably Prunus dulcis × peach hybrids such as 'Hall's Hardy' — extend viability into Zone 5 or 6, though kernel quality and shell characteristics differ somewhat from standard sweet almonds. See variety descriptions for specific zone ratings. The 2023 updated USDA Plant Hardiness Zone Map should be used for all zone references.
The bloom frost problem
Almonds are among the earliest-blooming deciduous tree crops. Bloom typically occurs in February–March in mild climates — before most other stone fruits, and well before the average last frost date in many locations. A single late frost event during full bloom can eliminate the entire season's crop. This is the primary reason almonds fail in many otherwise warm regions: the winters are mild enough for the tree to survive, but not consistent enough to protect early bloom.
The best almond sites share features with successful wine grape sites: moderate winter cold that satisfies chill requirements, then a dry, relatively frost-free spring with no late freezes, followed by heat. Valley floors where cold air pools on clear nights are problematic. Hillsides with good air drainage are ideal.
Chill hours
Almonds require winter chilling to break dormancy uniformly and bloom well. Most sweet almond varieties require approximately 200–500 chill hours (hours at or below 45°F) — one of the lower chill requirements among deciduous nut and fruit crops. This makes almonds suitable for mild-winter regions where higher-chill crops like apples and cherries struggle, but it also means almonds can break dormancy early in mild winters, increasing frost exposure risk. Specific variety chill requirements vary: consult your local cooperative extension office to determine typical accumulated chill hours at your site (UC ANR; WSU Extension).
Pacific Northwest tip
Almonds are a realistic option in specific PNW microclimates: the Willamette Valley, Rogue Valley, and similar inland locations where summers are warm and dry, late frosts are uncommon after bloom, and hull split can be completed before fall rains arrive. They are generally not well-suited west of the Cascades in western Washington and the coast ranges of Oregon, where cool, wet summers prevent proper hull development and fall rains arrive before nuts are fully dry. In suitable inland PNW locations, expect to harvest in late September through October. Contact your local OSU or WSU Extension office to assess your specific microclimate before planting almonds.
Variety selection and pollination
Variety selection affects not only flavor and shell type, but pollination requirements, bloom timing, and cold hardiness. Most standard almond varieties require cross-pollination — a second, bloom-compatible almond variety must be planted nearby for fruit set. Insects (primarily bees) are required to move pollen between trees.
⚠Pollination — most almonds are not self-fertile
Unlike some stone fruits, most almond varieties will not set meaningful crops from self-pollination alone (USU Extension). A second compatible almond variety must be planted within bee-flight range — generally within 100 feet with no solid barriers blocking bee movement. The two varieties must have overlapping bloom windows. Self-fertile exceptions exist: 'All-in-One' and 'Garden Prince' are both self-fertile semi-dwarf varieties suitable for smaller spaces, though yields are improved with a cross-pollinizer even for these (UC ANR; Dave Wilson Nursery).
| Variety | Type | Zone | Chill hrs | Notes |
|---|---|---|---|---|
| All-in-One | Self-fertile | Zones 8–9 | ~400 hrs | Semi-dwarf self-fertile variety; also cross-pollinates all other almond cultivars. Large sweet kernel; soft shell. Good choice for smaller spaces or single-tree planting. Requires warm summers for full nut development. (UC ANR; Dave Wilson Nursery) |
| Garden Prince | Self-fertile | Zones 7–9 | ~250 hrs | Compact self-fertile semi-dwarf; maintains 10–12 ft with summer pruning. One of the lowest-chill almond varieties available. Good ornamental value with pink spring bloom. Soft shell, sweet kernel. (UC ANR) |
| Nonpareil | Cross-pollinize | Zones 7–9 | ~400 hrs | The commercial standard — the variety most commonly found in stores. Excellent kernel quality; paper-thin shell; light skin; blanchable. Requires a cross-pollinizer (pair with All-in-One or Mission). Blooms early; moderately susceptible to bloom frost. (UC ANR; Dave Wilson Nursery) |
| Mission (Texas) | Cross-pollinize | Zones 7–9 | ~400–500 hrs | Blooms later than Nonpareil, reducing frost risk; often planted as a pollinizer for Nonpareil. Hard shell; strong distinctive flavor. Good keeper. Requires a cross-pollinizer. (USU Extension; UC ANR) |
| Hall's Hardy | Self-fertile | Zones 5–9 | ~200–400 hrs | A peach-almond hybrid; the hardiest commercially available variety, rated to Zone 5. Self-fertile. Hard shell; kernels have a slightly bitter edge compared to standard sweet almonds. Good ornamental value; showy pink spring flowers. Suitable for colder climates where standard varieties fail. (USU Extension) |
When planting varieties that require cross-pollination, plant both trees in the same general area and ensure bloom timing overlaps. Position pollinizers no more than 100 feet from the variety they are serving, with no solid barriers impeding bee movement between them.
Rootstocks and tree size
Raintree's almond trees are grafted on one of two rootstocks, each influencing final tree size and preferred soil conditions:
| Rootstock | Mature size | Best soil pH | Notes |
|---|---|---|---|
| Lovell Peach | 15–20 ft tall and wide (maintained) | 6.3–6.8 | Vigorous, drought-tolerant once established. Good nematode resistance. Standard rootstock for most almond production. Best in well-drained loam or sandy loam. |
| Marianna 2624 Plum | 12–15 ft tall and wide (maintained) | 6.8–7.2 | More dwarfing than Lovell; tolerates heavier, wetter soils better. Shallow-rooted; requires staking until established. Better suited to heavier clay soils. |
Check your individual tree's label to confirm rootstock and match soil amendment and pH targets accordingly. Almonds generally do not perform well in containers long-term — trees on both rootstocks grow too large and vigorous for sustained container culture.
Site selection and soil
Choosing a site
Almonds need a minimum of 8 hours of direct sunlight measured in early summer (late June through early August). Sunlight drives flower bud initiation for the following season and is essential for kernel development and hull splitting in the current season. A site that receives less than 8 hours of summer sun will produce disappointing yields regardless of other factors.
Avoid low-lying frost pockets — areas where cold air drains and pools on still, clear nights. These are the most dangerous sites for almond bloom. A slight slope with good cold-air drainage, ideally south or southwest facing to maximize heat accumulation, is the best choice for almonds in the PNW and other marginal-climate locations.
Almonds are notably drought-tolerant once established, but they require well-drained soil. Poor drainage — particularly standing water in winter — is one of the most common causes of almond decline and death. Avoid low spots, compacted soils, or sites where water pools after rain. In heavy clay soils, raised beds or mounded planting hills improve drainage significantly.
Soil preparation
Preferred soil pH depends on rootstock (see table above). Test your soil before planting and amend if needed: ground limestone to raise pH in acidic soils; elemental sulfur to lower it in alkaline ones. Work 1–2 inches of plant-based organic matter (compost, aged wood chips) into the planting area 1.5–2 times the diameter of the planting hole and up to one foot deep. Do not add concentrated fertilizer directly to the planting hole — it can burn young roots. Apply a 2–4 inch mulch layer immediately after planting, keeping mulch pulled back 4–6 inches from the trunk.
âš Almonds and wet winters
Almonds are highly susceptible to crown rot (Phytophthoraspp.) in poorly drained or chronically wet soils. This is a leading cause of almond failure in the maritime PNW west of the Cascades. If your site has any drainage issues, plant on a raised mound 12–18 inches above the surrounding grade and ensure runoff can drain freely away from the planting area. Do not plant almonds in any location where water stands for more than 24 hours after rain. (UC ANR; OSU Extension)
Watering and feeding
Almonds are more drought-tolerant than most stone fruits, but consistent moisture during establishment (first 2 seasons) and during kernel development (summer) is important for tree health and yield. Target approximately 1 inch of water per week over the root zone during the growing season — about 7–10 gallons per week for a typical 3-foot-diameter planting area. Water deeply once or twice weekly rather than lightly each day; this develops a deep, drought-tolerant root system. Allow the top inch or two to dry between waterings.
In the PNW, spring rainfall typically covers irrigation through May or June. Supplemental irrigation from July through harvest is critical for kernel filling and hull split. In well-established trees in moderate climates, almonds will tolerate dry spells better than most stone fruits, but sustained drought during kernel development reduces yield and quality. Drip irrigation is ideal for delivering water to the root zone while keeping foliage dry — wet foliage in almond is a significant contributor to fungal disease.
Fertilize with an all-purpose or fruit-tree fertilizer in early spring, or apply 2–3 inches of well-rotted compost over the root zone annually. Do not apply nitrogen fertilizers after early summer — late-season nitrogen encourages soft new growth vulnerable to winter cold and disease. As a general guide: if the tree is producing one foot or more of new growth annually and the foliage is healthy and deep green, little or no fertilizer may be needed.
Pruning and training
Establishing an open-vase form
The traditional training system for almonds (and most stone fruits) is the open-center or vase form: 3–5 main scaffold branches arising from a short trunk, with no central leader. This form allows sunlight and air to penetrate the canopy — critical for disease control in the humid PNW and for uniform nut ripening. Begin establishing the vase structure in the first year by selecting 3–5 evenly spaced scaffold branches and removing the central leader to encourage outward growth. Remove competing upright growth.
Annual dormant pruning
Prune almonds during full dormancy — late winter, typically February in the PNW, after the coldest weather has passed but before bud swell. Remove crossing or rubbing branches, water sprouts growing straight up from main scaffolds, and any dead or diseased wood. Thin the canopy to maintain airflow and light penetration. Almonds fruit on spurs (short fruiting branches that persist for years) as well as on one-year-old wood; both should be preserved in a productive tree.
âš Avoid winter pruning wounds in wet weather
In the PNW, pruning cuts made in wet weather during late fall and early winter are significantly more susceptible to bacterial canker (Pseudomonas syringae), a serious disease of stone fruits in high-rainfall regions. Prune during a dry window in late winter — February is generally safer than November or December for stone fruits in western Oregon and Washington. Allow cuts to dry quickly. (OSU Extension; WSU Extension)
Summer pruning
Light summer pruning — removing water sprouts, thinning dense growth, and opening the canopy — improves air circulation and reduces disease pressure in humid climates. Summer pruning does not replace winter pruning but helps manage vigorous growth and improves the following year's fruit wood.
Harvest and curing
Almonds are ready to harvest when the hull (outer green husk) begins to split open naturally. This split signals that the nut inside has finished developing and the kernel has hardened. Do not harvest before hulls begin to split — the kernel will still be too moist and will not store well. In the PNW, hull split typically occurs in late September to October in suitable inland locations; earlier in California's Central Valley (late August to September).
Once hulls are splitting, harvest promptly: delay allows rain damage and hull rot fungi to damage the nuts, and birds will begin taking them. In commercial production, trees are mechanically shaken; in the home garden, spread a tarp and use a long pole to strike scaffold branches, or simply collect nuts after they fall naturally.
Remove the hull from harvested nuts immediately — hull tissue left in contact with the shell accelerates mold. Spread shelled nuts in a single layer in a warm, well-ventilated location and allow them to dry for 1–2 weeks until the kernel snaps cleanly when bitten. Store dried almonds in a cool, dry location in mesh or paper bags (not sealed plastic) — they will keep for up to a year at room temperature and longer refrigerated.
Common problems
Bacterial Canker
High — serious in PNW
Pseudomonas syringae— causes sunken, darkened cankers on branches and trunk with amber gum ooze; wilting and death of branches above the canker. Especially severe when bark is wounded by frost or when pruning is done in wet winter weather. Newly planted trees are most susceptible.
Bacterial canker — amber gum oozes from infected bark and branch cankers (shown on cherry; the same gummosis affects almond). Photo: Rosser1954 (CC BY-SA 3.0), via Wikimedia Commons — resized.
- Apply copper fungicide in early fall and again in January to protect wounds and reduce inoculum
- Prune only during dry weather in late winter; avoid pruning November through January in western WA and OR
- Remove infected branches well below the canker margin; disinfect tools between cuts
- Maintain tree vigor — stressed trees are far more susceptible
Peach Leaf Curl
Moderate — preventable
Taphrina deformans— blisters and deforms new leaves, turning them reddish and eventually causing them to drop. Almonds share susceptibility with peaches and nectarines. Infection occurs during wet spring conditions when leaves are emerging.
Leaf curl — new leaves redden, thicken, pucker, and distort (shown on peach; almond is also susceptible to Taphrina deformans). Photo: eyrezer (CC BY 4.0), via Wikimedia Commons — resized.
- Apply lime-sulfur or copper fungicide starting in mid-December; repeat at 3–4 week intervals through bud swell
- Covering trees with rain-exclusion fabric from December through bloom prevents infection by keeping bark and emerging buds dry
- Control timing varies with climate — contact your local extension office for region-specific spray timing
Brown Rot
Moderate — wet springs
Moniliniaspp. — wilts and kills blossoms and shoot tips; infected nuts turn brown and may hang as "mummies." Blossom brown rot is worst in wet spring weather during and after bloom.
Brown rot — fruit and blossoms rot, shrivel, and erupt in tan-grey spore tufts (shown on peach, a close almond relative). Photo: m.borden (CC BY-SA 2.0), via Wikimedia Commons — resized.
- Promptly remove infected twigs and mummified nuts — they are the primary inoculum source
- Apply copper, sulfur, or lime-sulfur fungicide at petal fall; repeat in midsummer and fall if conditions are wet
- Maintain good canopy airflow through pruning; wet foliage is high-risk
Shot Hole Disease (Coryneum Blight)
Moderate — spray preventable
Small reddish-purple spots on leaves that fall out, leaving characteristic holes. Twigs may develop spots and cankers. Spores spread by splashing water — common in PNW springs. Can also spot the nuts.
- Bordeaux mix or copper fungicide applied in early fall, winter, and spring
- Minimize overhead irrigation; keep sprinkler water off foliage
- Rake and remove fallen leaves in autumn to reduce overwintering inoculum
Scale (San José Scale, Calico Scale)
Moderate — monitor
Small barnacle-like bumps on branches and leaves; heavy infestations weaken limbs and reduce vigor. Most scale populations are manageable with dormant oil timed correctly.
- Dormant oil spray applied in early spring (before bud swell) disrupts overwintering scale populations
- Insecticidal soap or soap-oil spray during the juvenile "crawler" phase in late spring
- Avoid broad-spectrum insecticides during bloom — they kill beneficial insects that suppress scale and pollinate flowers
Deer and Rodents
High — protect young trees
Deer browse almond foliage and young growth; voles and mice chew bark at the base of trunks, particularly under mulch or snow cover in winter.
- 8-ft woven wire deer fence is most reliable protection in deer-pressure areas
- Wrap trunk bases with vinyl tree guards or hardware cloth from the ground up; check and replace as tree grows
- Keep mulch pulled back 4–6 inches from the trunk; keep vegetation cleared around the base
- Check for vole damage at trunk base in early spring after snow recedes
Seasonal care calendar
Winter
Dec - Feb
- Apply copper fungicide for bacterial canker and peach leaf curl prevention — early fall and January applications are most important
- Inspect and repair any deer or vole protection at the trunk base
- Do NOT prune in wet weather — hold pruning for a dry window in late winter
- Order pollinizer variety or additional trees early if needed
Late Winter
Feb – Mar
- Dormant pruning during a dry window — remove dead wood, water sprouts, and crossing branches; establish open-vase form on young trees
- Dormant oil spray for scale before bud swell
- Watch bloom closely — almond blooms early; frost protection (row cover) may be needed on nights below 28°F when flowers are open
- Do NOT apply insecticides during bloom — protect bees and other pollinators
Spring
Apr – Jun
- Apply fertilizer or compost to the root zone before leaves fully emerge
- Restore mulch layer to 2–4 inches; keep pulled back 4–6 inches from trunk
- Monitor for peach leaf curl and shot hole disease; apply copper or sulfur if conditions are wet and symptoms appear
- Begin irrigation if spring rains are insufficient
Summer
Jul – Aug
- Maintain regular deep irrigation through kernel development — dry spells during this window directly reduce yield and kernel quality
- Summer pruning: remove water sprouts, thin dense canopy growth, improve air circulation
- Monitor for scale, aphids, and mites; treat with targeted controls as needed
Harvest
Sep – Oct
- Check hulls daily — harvest when hulls begin splitting open naturally
- Spread tarp and strike scaffold branches to knock down nuts; or collect fallen nuts promptly
- Remove hulls immediately after harvest; spread nuts to dry in a warm, ventilated area for 1–2 weeks
- Test dryness: a kernel that snaps cleanly when bitten is ready for storage
Fall
Oct – Nov
- Apply first copper fungicide spray of the season for bacterial canker and peach leaf curl prevention (early fall application is critical)
- Apply fresh mulch layer; pull back from trunk
- Rake and remove fallen leaves — reduces overwintering disease inoculum
- Install or refresh trunk guards before winter