The ‘Lake Tahoe Dahlia’ is a popular choice for gardeners, known for its vibrant, elegant blooms. This dahlia cultivar features unique color transitions and substantial flower size, adding sophistication to garden designs.
Understanding the Lake Tahoe Dahlia
The ‘Lake Tahoe Dahlia’ produces large, decorative blooms with a sunset-like color palette. Flowers transition from soft yellow to rosy-pink or coral at the petal edges. Blooms can reach 5 inches in diameter. The plant grows 70 cm to 1 meter (2.3 to 3.3 feet) tall, with an upright, bushy habit and lush green foliage. Blooming begins in midsummer and continues until the first autumn frost.
Planting and Growing Lake Tahoe Dahlias
Growing ‘Lake Tahoe Dahlias’ requires proper site selection and soil preparation. They thrive in full sun, needing 6 to 8 hours of direct sunlight daily for best blooms. Well-draining soil is crucial, as dahlias are susceptible to rot. An ideal soil pH ranges from 6.0 to 7.5, with 6.5 to 7 being preferable. Amending heavy clay soils with compost or organic matter improves drainage and aeration.
Planting
Plant tubers after the last spring frost, when soil temperatures reach 60°F (15°C). Dig a 4 to 6-inch deep hole, place the tuber with the “eye” facing up, and cover with a few inches of soil. Space smaller varieties 12 inches apart; larger varieties may need up to 3 feet for air circulation.
Watering
Watering supports healthy dahlia growth, especially during dry spells and bloom development. After planting, avoid watering tubers until green sprouts emerge to prevent rot. Once sprouted, water dahlias once or twice weekly, ensuring deep watering that reaches the root system. Maintain consistent moisture, but avoid overwatering, which causes yellowed or mushy leaves.
Fertilization
Dahlias are heavy feeders and benefit from consistent fertilization for blooms. A phosphorus-rich fertilizer (e.g., 5-10-5 or 10-20-20) promotes flowering. Apply fertilizer every 3 to 4 weeks from sprouting through midsummer. Too much nitrogen encourages leafy growth over flowers, so use a low-nitrogen fertilizer once plants are established.
Staking and Deadheading
‘Lake Tahoe’ dahlias grow tall with large, heavy blooms, requiring staking. Insert stakes at planting time to avoid disturbing roots later, and gently tie stems to the support as the plant grows. Regular deadheading (removing spent blooms) encourages continuous flowering. Snip faded flowers just above a healthy set of leaves or buds to direct the plant’s energy towards producing new blooms rather than setting seeds.
Winter Care for Lake Tahoe Dahlias
In colder climates, ‘Lake Tahoe Dahlias’ are not winter-hardy; tubers must be dug and stored indoors. Begin this process after the first hard frost, which signals dormancy. Cut plant stems back to about 3 to 4 inches above the ground on the day you plan to dig them.
Excavating and Curing
When digging tubers, carefully excavate at least 1 foot from the stem to avoid damaging tuber necks. Gently remove excess soil from the tubers. Air dry tubers for several days to a week away from direct sunlight and freezing temperatures; this curing prevents rot during storage.
Storage
Store cleaned, cured tubers in a cool, dark, frost-free location with good air circulation (e.g., basement or unheated garage). Ideal storage is 40-50°F (4-10°C) with 75%-85% humidity to prevent shriveling or rotting. Storage mediums like peat moss, vermiculite, or wood shavings can be used to layer tubers in cardboard boxes or plastic containers. Periodically check stored tubers and remove any showing signs of rot or shriveling. If tubers shrivel, a light misting or moving them to a more humid location can help.
Common Challenges and Solutions
Dahlias can encounter various pests during their growing season.
Pests
Slugs and snails are problematic for young dahlia foliage, leaving irregular holes. Apply slug bait or patrol at night to remove them.
Aphids, small soft-bodied insects, cluster on new growth, causing yellowing or stunted development by sucking plant sap. Insecticidal soap or neem oil applications can control aphids, and encouraging natural predators like ladybugs is beneficial.
Spider mites thrive in hot, dry conditions, causing stippled or discolored leaves. Manage them by hosing plants or using miticides for severe cases.
Earwigs and caterpillars chew on leaves and petals; remove them by hand or trap with rolled-up newspaper.
Diseases
Several diseases can affect dahlias, often related to environmental conditions. Powdery mildew appears as a white, powdery substance on leaves, especially in warm, humid climates. Good air circulation and avoiding overhead irrigation can help prevent it. Botrytis (gray mold) causes brown, rotting spots on flowers and leaves, particularly in cool, wet conditions. Prompt removal of infected plant parts and maintaining plant cleanliness reduces its spread. Viral issues, like dahlia mosaic virus, cause mottled or distorted leaves, often spread by insects such as aphids or thrips. Preventing insect infestations and destroying infected plants helps contain viral diseases.
Lack of Blooms
A lack of blooms can occur. Insufficient sunlight is a common cause; dahlias require 6 to 8 hours of direct sun daily to flower well. Over-fertilization with nitrogen can lead to lush foliage but few flowers, as the plant prioritizes leaf growth. Inconsistent watering (too much or too little) can also hinder blooming. Leggy growth (long, spindly stems) often results from insufficient light as the plant stretches for sun. Pinching back the central stem of young plants encourages bushier growth and more flower stems.