Ages 18-24? Explore Prime for Young Adults and see if you are eligible

Best Month to Plant Ginger for Thriving Growth

Getting the best month to plant ginger right can mean the difference between a disappointing harvest and a bumper crop of plump, aromatic rhizomes. Ginger is a tropical plant that craves warmth, hates frost, and demands a long, consistent growing season. Planting too early in cold soil leads to rot and stalled growth; planting too late cuts the season short and reduces yields. For most gardeners, that sweet spot falls in late spring, once soil temperatures consistently stay above 68°F and all danger of frost has passed.

Whether you are growing ginger in raised beds, containers, or directly in the ground, using the right products can make the process smoother. Below, we round up 8 ginger root options—from culinary ginger to ornamental shampoo ginger—that help you start strong during the best planting window. For more general plant care advice, check out our Plant category.

1
Prime Best Seller

GreenhousePCA Fresh Culinary Ginger Root Plant

GreenhousePCA
9.3 /10
TYG Score
TYG Score is calculated based on product ratings, reviews, and sales performance to help you make informed purchasing decisions. Learn more ›
These GreenhousePCA ginger starts are live rhizomes from Peru, selected for planting rather than eating. While most customers see good sprouts with patience, a few report shriveled or moldy pieces, so quality can vary. Best for beginners wanting a low-maintenance, renewable ginger supply.
Pros & Cons

Pros

  • Very easy to plant with clear instructions included
  • Can grow indoors year-round with bright, indirect light
  • Provides a renewable source of fresh ginger for cooking and teas
  • Suitable for both container and in-ground gardening
  • Many reviewers report successful sprouting and healthy plants

Cons

  • Some rhizomes may arrive shriveled or moldy, as noted in customer reviews
  • Requires patience - sprouts can take weeks to appear
  • Not all pieces may sprout; success depends on soil moisture and temperature
Detailed Review

The GreenhousePCA Fresh Culinary Ginger Root Plant Starts are exactly what they sound like: live ginger rhizomes meant for planting, not eating straight from the box. Each order includes multiple pieces sourced from Peru, selected for their ability to sprout and grow into new ginger plants. This is a great option for home gardeners who want a steady supply of fresh ginger for sushi, stir-fries, teas, and other recipes without relying on store-bought roots that may be treated with growth inhibitors.

The standout feature here is simplicity. You don't need a green thumb or special equipment. Just plant the rhizomes 1-2 inches deep in loose, well-draining soil with the buds facing up, keep the soil consistently moist but not soaked, and provide warm conditions with indirect light. The ginger will send up shoots over time, then develop a network of underground rhizomes that can be harvested selectively. Many customers report seeing sprouts within two to four weeks, though some needed a couple of months of patience. The plants grow into attractive, bamboo-like foliage that adds a tropical look to your patio or windowsill.

Design and build quality vary based on the individual rhizomes. Most arrive in good condition with visible growth points, but a handful of reviewers received pieces that were shriveled, spongy, or moldy. This seems to be an occasional issue rather than the norm. The product is marketed as fresh and viable, and most buyers confirm it works well when planted promptly and given proper care. The rhizomes are not huge, but they are active and ready to grow.

The main drawbacks are inconsistency and the need for patience. Some users had no sprouts at all, while others saw great results. Overwatering can lead to rot. Also, ginger takes several months to reach a harvestable size, so this is not an instant gratification project. It works best for gardeners who enjoy the process and don't mind waiting.

Overall, the GreenhousePCA ginger starts deliver on their promise of easy, homegrown ginger for most people. The price is reasonable for three live rhizomes, and the potential for a self-renewing crop is a big plus. If you want fresh ginger on demand and are okay with a little trial and error, these are a solid buy.

2
Prime Editor's Pick

FamPlants Ginger Root Plant (4 Pack)

FamPlants
9.1 /10
TYG Score
TYG Score is calculated based on product ratings, reviews, and sales performance to help you make informed purchasing decisions. Learn more ›
This 4-pack of live ginger root plants from FamPlants is a great starting point for home cooks and gardeners who want a steady supply of fresh, organic ginger. While some plants may arrive small or struggle without careful care, they offer a rewarding harvest of spicy rhizomes perfect for teas, stir-fries, and remedies.
Pros & Cons

Pros

  • Live plants arrive in good condition, with many reviewers noting healthy, intact starts.
  • Versatile for cooking, tea, and medicinal use, adding fresh flavor and anti-inflammatory benefits.
  • Easy to grow in containers, perfect for small spaces and indoor gardening.
  • Perennial nature means once established, you can harvest year after year.
  • Non-GMO and organic-friendly, appealing to health-conscious gardeners.

Cons

  • Some plants may arrive small or with dry, brown leaves, requiring extra care to survive.
  • A few buyers reported plants dying within weeks, especially if not repotted promptly or kept in ideal conditions.
  • Instructions for care could be more detailed, as some users found the plants finicky to maintain.
Detailed Review

The FamPlants Ginger Root Plant 4-Pack offers a convenient way to start your own organic ginger patch at home. These live Zingiber officinale plants are perfect for home cooks, tea lovers, and gardeners who want a reliable source of fresh, spicy rhizomes. Whether you grow them in a raised bed, container, or indoor pot, this set gives you four vigorous starts to get going.

The standout quality here is the freshness and flavor. Homegrown ginger has a pungent, aromatic kick that store-bought rhizomes often lack. Many buyers reported receiving healthy, intact plants that quickly established after repotting. The plants thrive in partial shade and warm, humid conditions, making them a good fit for both indoor and outdoor setups. They are also non-GMO and chemical-free, which appeals to organic gardeners.

However, not all experiences have been smooth. Some users noted that the plants arrived small with brown leaves, and a few struggled to survive past the first month. This seems to depend on how quickly they were repotted and whether they got consistent moisture and warmth. The lack of detailed care instructions in the package was a common complaint, so beginners may need to research ginger growing tips separately.

Despite these drawbacks, the majority of reviews are positive, with many customers praising the plants' vigor and the value of growing your own ginger. The 4-pack is reasonably priced for live plants, and the perennial nature means you can harvest year after year with proper care. Just be prepared to give them a little extra attention during the first few weeks.

Overall, this is a solid choice for anyone who wants to grow fresh ginger at home. If you have a warm spot with well-drained soil and are willing to follow basic care guidelines, these plants will reward you with a bountiful harvest. Just manage expectations on size and initial survival, and you will enjoy homegrown ginger that elevates your cooking and teas.

3
Prime Limited Time

Greenhouse PCA 10 Live Sprouted Heirloom Peruvian

GreenhousePCA
8.9 /10
TYG Score
TYG Score is calculated based on product ratings, reviews, and sales performance to help you make informed purchasing decisions. Learn more ›
This set of 10 fresh Peruvian ginger rhizomes is marketed as live and sprout-ready for home cultivation. Many users successfully grow flavorful ginger, but inconsistent sprouting and occasional poor packaging make results unpredictable.
Pros & Cons

Pros

  • Fresh, viable rhizomes sourced from Peru
  • Easy planting process with minimal equipment needed
  • Can be grown indoors or outdoors in warm conditions
  • Produces a steady supply of ginger for harvesting and replanting
  • Taste is highly praised by successful growers

Cons

  • Some rhizomes arrive dry, unsprouted, or shriveled
  • Sprouting success is not guaranteed, especially in cold climates
  • Customer service may be slow to respond to issues
  • Not all pieces may sprout, requiring patience and ideal conditions
Detailed Review

The Greenhouse PCA 10 Live Sprouted Heirloom Peruvian Ginger Rhizomes offer a way to grow your own fresh ginger at home. This product is aimed at beginners and experienced gardeners alike, especially those interested in self-sufficiency and home food production. Each rhizome is selected for planting and is not chemically treated to prevent sprouting, a common issue with store-bought ginger.

The standout benefit is the simplicity of planting: just bury the rhizome an inch or two deep in loose soil with the growth points up, keep it warm and moist, and wait. The heirloom variety is praised for its strong, spicy flavor, ideal for teas, stir-fries, and baking. Many reviewers reported robust growth and a satisfying harvest after a few months.

However, real-world performance is mixed. While some customers received beautiful, already-sprouting pieces and enjoyed a bountiful harvest, others found the rhizomes dry, unsprouted, or moldy. The lack of consistent quality control is a significant concern. Positive reviews highlight the taste and renewable nature of the crop, while negative ones point to disappointment when none of the ten pieces sprouted.

Drawbacks include the need for warm temperatures (above 70°F) and patience, as sprouting can take weeks. Some users in colder zones struggled to get growth even with indoor setups. Customer service responsiveness also appears to be hit-or-miss, with some complaining about lack of support.

In summary, this product can be a great investment if you are willing to accept some risk. For gardeners in warm climates or with indoor grow setups, the potential for a continuous supply of fresh, organic-tasting ginger is real. But for those expecting guaranteed results, the inconsistent quality may be frustrating. Proceed with realistic expectations and a backup plan.

Specifications

Package Dimensions: 8.5 x 6.22 x 3.11 inches
Item Weight: 0.635 ounces
Manufacturer: Greenhouse PCA
ASIN: B0B7Q7X5SJ
Item Form: Plant bulb
Unit Count: 10
Number of Items: 1
Produce sold as: Loose

4
Prime Top Rated

AKTRD 5 Shampoo Ginger Roots (Zingiber Zerumbet)

AKTRD
9.9 /10
TYG Score
TYG Score is calculated based on product ratings, reviews, and sales performance to help you make informed purchasing decisions. Learn more ›
This five-pack of live shampoo ginger rhizomes from AKTRD lets you grow a tall, tropical ornamental that produces pinecone-like blooms with a natural shampoo liquid. Ideal for gardeners in zones 8-11 or anyone wanting a unique container plant indoors.
Pros & Cons

Pros

  • Includes five live rhizomes ready to plant, ensuring a good start.
  • Can be grown both indoors and outdoors, offering flexibility.
  • Ornamental value with tall foliage and striking pinecone-like blooms.
  • Natural hair care ingredient from the flower bracts.

Cons

  • Requires consistent moisture and rich soil, which may be a challenge for some gardeners.
  • Outdoor growth is limited to USDA zones 8-11; colder areas need indoor overwintering.
  • No customer reviews yet, so actual plant size and vigor are unverified.
Detailed Review

AKTRD's Shampoo Ginger Roots offer a unique way to bring a tropical touch to your garden or home. This set includes five live Zingiber zerumbet rhizomes, also known as pinecone ginger or awapuhi. The plant is prized for its tall stalks that can reach 3 to 6 feet and its distinctive pinecone-shaped flower bracts. These bracts contain a fragrant, soapy liquid that has been traditionally used as a natural shampoo and conditioner. Whether you are an experienced gardener or a beginner looking for something unusual, these rhizomes are a solid choice.

In terms of real-world performance, the rhizomes are easy to plant and establish. They prefer rich, well-draining soil that stays consistently moist. Partial shade to full sun works well, so you have flexibility in placement. In USDA zones 8 through 11, you can grow them outdoors year-round. If you live in a cooler climate, you can keep them in a container and move them indoors during winter. Once settled, the plants grow quickly and produce multiple shoots, creating a lush clump over time. The flowers appear in late summer to fall, adding a tropical flair that draws attention.

The build quality of these rhizomes is standard for live plants. They arrive as dormant or semi-dormant rhizomes, ready to be potted or planted directly. AKTRD packages them carefully to prevent damage during shipping. The dimensions of the package (7 x 8 x 9 inches) suggest a compact box that fits easily in a mailbox or at your door. As with any live plant product, the condition upon arrival can vary depending on handling and weather, but the company seems to take reasonable care.

One potential drawback is that these rhizomes demand consistent moisture and rich soil. If you tend to forget watering or have poor soil, you may need to amend it or set up a regular watering schedule. Also, outdoor cultivation is limited to warmer zones; northern gardeners will need to bring pots inside or dig up rhizomes for winter storage. Since there are no customer reviews yet, it's hard to gauge the typical size and vigor of the rhizomes, but the description matches standard Zingiber zerumbet characteristics.

Overall, AKTRD's Shampoo Ginger Roots are a great buy for anyone wanting an ornamental plant with a practical bonus. The five-rhizome pack gives you enough to start a small patch or share with friends. If you enjoy tropical plants and natural hair care, this product delivers both beauty and utility. Just be prepared to give it the moisture and warmth it needs, and you will have a conversation piece in your garden or living room.

5
Prime

HILROQG 6 Awapuhi Shampoo Ginger Roots

HILROQG
9.3 /10
TYG Score
TYG Score is calculated based on product ratings, reviews, and sales performance to help you make informed purchasing decisions. Learn more ›
This pack of six fresh Awapuhi rhizomes offers a great way to start your own tropical shampoo ginger plants, especially if you live in zones 8-11. Most buyers report healthy, clean roots that sprout well, though a few did not see growth, so success may depend on your specific growing conditions. Ideal for gardeners wanting a unique, fragrant flower with natural hair-care uses.
Pros & Cons

Pros

  • Healthy, intact rhizomes upon delivery according to most reviews
  • Versatile growing options: outdoor garden, greenhouse, or indoor pot
  • Unique ornamental flower with practical uses (natural shampoo)
  • Good value for six roots at a reasonable price point
  • Moderate care requirements suitable for intermediate gardeners

Cons

  • Some customers reported the rhizomes did not sprout despite following instructions
  • Not frost-tolerant; requires protection or indoor overwintering in zones below 8
  • May take time to establish and bloom; patience is needed
Detailed Review

The Awapuhi Shampoo Ginger (Zingiber zerumbet) is a tropical perennial that brings both beauty and utility to your garden. This pack from HILROQG includes six fresh rhizomes, each capable of producing a plant that reaches 3-6 feet tall with striking pinecone-shaped flower bracts. It's an excellent choice for gardeners in USDA zones 8-11 or anyone willing to grow it indoors or in a greenhouse. The plant's common name comes from the clear, fragrant liquid found in the flower heads, which has been used traditionally as a natural shampoo and conditioner.

Based on customer reviews, the rhizomes generally arrive in good condition, healthy, and clean. Several buyers noted that they received extras and that their plants sprouted within weeks when given regular watering and partial sun. However, a few customers experienced no growth at all, despite following the planting instructions carefully. This suggests that while the product is reliable for many, success can vary based on soil quality, temperature, and moisture levels. It's worth noting that ginger rhizomes can be sensitive to overwatering or cold snaps, so proper care is essential.

The design and packaging of these rhizomes are straightforward. They come fresh and ready to plant, with no special treatment needed. The roots are firm and show no signs of mold or damage, which speaks to the seller's handling and shipping process. One reviewer mentioned the seller communicated well regarding shipping, adding a layer of trust. For best results, plant the rhizomes in well-draining soil with moderate moisture and provide dappled sunlight or morning sun with afternoon shade.

A potential drawback is that this plant is not cold-hardy. If you live outside zones 8-11, you'll need to bring it indoors during winter or grow it in a container that can be moved. Also, the plant takes time to establish and may not flower in its first season, so patience is required. The mixed reviews on germination are a reminder that gardening always has an element of unpredictability, but the majority of feedback is positive.

Overall, the HILROQG Awapuhi Shampoo Ginger roots are a solid pick for gardeners looking to add a unique, functional tropical plant to their collection. The price is fair for six roots, and the potential for beautiful blooms and natural hair care benefits makes it a worthwhile experiment. I recommend it for intermediate gardeners who understand the needs of tropical plants and are ready to provide the right environment. With proper care, these rhizomes can turn into a stunning conversation piece in your garden or home.

6
Prime

JAMAICAN GINGER Zingiber officinale

Unknown
9.4 /10
TYG Score
TYG Score is calculated based on product ratings, reviews, and sales performance to help you make informed purchasing decisions. Learn more ›
These Jamaican ginger rhizomes offer an intense, fresh flavor that surpasses store-bought varieties. Ideal for gardeners wanting to grow their own ginger indoors or outdoors, but success may vary depending on planting conditions.
Pros & Cons

Pros

  • Intense, fresh ginger flavor that grocery store roots often lack
  • Healthy, plump rhizomes upon arrival according to many buyers
  • Can be grown both indoors and outdoors with moderate watering
  • Good value for the price compared to buying small ginger plants
  • Versatile: use for cooking, pickling, tea, or planting for a continuous harvest

Cons

  • Some rhizomes may not sprout if planted in cold or overly wet conditions
  • A few customers reported receiving slightly less than the advertised 1 pound
  • Success rate depends on proper soaking and warm soil temperatures
Detailed Review

The Jamaican Ginger root offered here is a 1-pound bundle of Zingiber officinale rhizomes meant for growing or culinary use. It's a product that appeals to home gardeners who want to cultivate their own fresh ginger, as well as cooks who prize the superior flavor of non-supermarket ginger. The package includes multiple rhizome pieces, and the instructions are simple: soak them overnight in warm water, then plant in a rich, well-draining pot or garden bed with partial shade.

Standout features include the rhizomes' freshness and the intense, spicy kick they deliver. Verified buyers describe the taste as amazing and much more pungent than typical grocery store ginger. The ability to grow indoors or outdoors adds flexibility for those with limited space or colder climates. Many customers successfully sprouted their ginger after a bit of patience, and the resulting plants grew well. The root can also be used directly for cooking, pickling, or making tea right out of the box.

Design and build quality are straightforward: these are natural, untreated rhizomes. They arrive plump and moist, which signals good freshness. The product is plant-based and free from synthetic growth inhibitors often found on imported ginger. However, a few users noted that the rhizomes were slow to sprout or didn't sprout at all, especially if temperatures were too low or if they received too much water. One reviewer also reported receiving 15 ounces instead of 16, which is a slight shortfall worth checking upon delivery.

Potential drawbacks center on the variable germination rate. While many enjoy a high success rate, others lost most of their roots due to unfavorable conditions or possibly older stock. The lack of a branded manufacturer may also raise questions about consistency. For best results, follow the planting guidelines closely and consider starting in a warm indoor environment before moving outdoors.

Overall, this Jamaican Ginger bundle offers excellent flavor and a satisfying gardening experience for those willing to follow basic care steps. It's a solid choice for anyone wanting a reliable source of fresh ginger at home. Just be prepared for a few rhizomes to fail if conditions aren't perfect, and weigh the package upon arrival to ensure you get the full pound.

7
Prime

20 Wild Ginger Roots (Asarum canadense)

Generic
9.9 /10
TYG Score
TYG Score is calculated based on product ratings, reviews, and sales performance to help you make informed purchasing decisions. Learn more ›
This pack of 20 wild ginger roots offers a reliable way to turn shady, problem areas into a lush green carpet. The large heart-shaped leaves suppress weeds naturally, and the hidden burgundy flowers add a fun surprise. Ideal for gardeners seeking a low-maintenance native ground cover.
Pros & Cons

Pros

  • Thrives in challenging shady spots where grass and other plants fail
  • Natural weed suppression reduces garden maintenance
  • Unique hidden flowers add an element of discovery
  • Low maintenance once established, ideal for busy gardeners
  • Native species supports local ecosystems and pollinators

Cons

  • Flowers are hidden beneath leaves, so not a showy bloom display
  • May take a full growing season to establish dense coverage
  • Requires consistent moisture during dry periods for optimal growth
Detailed Review

Wild Ginger (Asarum canadense) is a native North American ground cover that thrives in the shadiest corners of your landscape. This 20-pack of live roots is designed for gardeners who struggle with bare, shady spots where grass refuses to grow. Whether you have a woodland garden, a slope under trees, or a north-facing foundation bed, these plants offer a reliable solution that turns problem areas into lush, green carpets.

The standout feature is the large, heart-shaped leaves that spread quickly to form a dense mat. This living carpet naturally suppresses weeds, so you can say goodbye to constant mulching and weeding. As a bonus, the plants produce unique burgundy flowers that bloom in spring, tucked right beneath the foliage. They are not showy from a distance, but discovering them up close adds a charming element of surprise for anyone exploring the garden.

In terms of build quality, the roots arrived healthy and ready to plant, as noted by early buyers. The plants are GMO-free and suited for partial to full shade. They prefer moist, well-drained soil but are remarkably adaptable once established. The foliage provides year-round texture, dying back in winter and returning each spring. This is a low-maintenance choice for anyone who wants a natural, woodland aesthetic without constant upkeep.

One potential drawback is that the flowers are hidden beneath the leaves, so if you are looking for a showy bloom display, this may not be the plant for you. Additionally, coverage can take a season to fully fill in, especially if planted in dry conditions without supplemental watering. However, for the price and the number of roots included, this pack offers excellent value for covering medium to large shaded areas.

Overall, Wild Ginger roots are a smart investment for gardeners who want to reclaim shady, difficult spots with a native plant that practically takes care of itself. The combination of weed suppression, low maintenance, and hidden floral surprises makes it a standout choice for woodland gardens, slopes, and foundation plantings. If you have a shady area that needs a reliable ground cover, this pack is worth serious consideration.

8
Prime

4 Fresh Awapuhi Red Shampoo Ginger Roots

PlantsSeedsBulbs
9.0 /10
TYG Score
TYG Score is calculated based on product ratings, reviews, and sales performance to help you make informed purchasing decisions. Learn more ›
These are 4 fresh red shampoo ginger rhizomes (Zingiber zerumbet) ideal for outdoor planting in zones 9-11. They produce unique pinecone-shaped red bracts and fragrant ginger lily flowers, but some buyers have reported receiving dried-out roots.
Pros & Cons

Pros

  • Produces eye-catching red pinecone-like bracts and fragrant ginger lily flowers
  • Low maintenance and easy to grow in warm climates
  • Can be used for natural hair care
  • Fresh rhizomes have good growth potential if handled properly
  • Adds tropical flair to gardens and containers

Cons

  • Some buyers have received dried-out rhizomes that may not sprout
  • Only hardy in zones 9-11; requires winter protection in colder areas
  • Limited customer reviews make it hard to gauge overall satisfaction
Detailed Review

If you are looking for a conversation-starting plant that doubles as a natural hair care ingredient, the PlantsSeedsBulbs 4 Shampoo Ginger Roots might be exactly what you need. These are live, 1-year-old rhizomes of Zingiber zerumbet, also known as awapuhi, red ginger, or pinecone ginger. They are sold for outdoor planting in warm climates and promise to produce striking red bracts that resemble pinecones, along with fragrant white ginger lily flowers.

The standout feature here is the plant's unique appearance and dual purpose. In the garden, shampoo ginger grows into a lush, tropical-looking perennial that can reach 3 to 5 feet tall. The red bracts eventually open to reveal small white flowers. And yes, the name is not just for show: the rhizomes contain a natural saponin that can be used as a gentle shampoo or body wash. It is a fun, practical addition for anyone who enjoys natural living or wants to impress guests with an unusual plant.

However, the product does have a significant drawback based on early feedback. One customer reported that the rhizomes arrived dry as a bone, which is a major concern because dried rhizomes are unlikely to sprout. Freshness is critical for live plant materials, and inconsistent handling during shipping can kill the roots before they even reach you. If you decide to buy, inspect the rhizomes immediately upon arrival and contact the seller if they feel brittle or shriveled.

On the plus side, these are relatively low-maintenance plants once established. They prefer partial shade to full sun and thrive in consistently moist soil. They are hardy only in USDA zones 9 through 11, so gardeners in cooler regions will need to grow them in containers and bring them indoors during winter. The price point of around $15 for four rhizomes is reasonable for a live plant that offers both ornamental and practical value.

Overall, shampoo ginger is a fascinating plant with real appeal for adventurous gardeners and natural beauty enthusiasts. The main risk is receiving dried-out rhizomes, so consider purchasing from a seller with a strong reputation for fresh plant material. If you get healthy roots, you will likely enjoy a rewarding, low-fuss plant that keeps on giving.

Frequently Asked Questions About the Best Month to Plant Ginger

1. What is the best month to plant ginger in the US?
For most of the United States, April or May is ideal, once the soil has warmed to at least 68°F and frost is no longer a threat. In warmer zones (9-11), you can start as early as March. Always check your local frost dates and use a soil thermometer for accuracy.

2. Can I plant ginger indoors before the best month?
Yes, starting ginger indoors 4-6 weeks before your outdoor planting date gives you a head start. Place rhizomes in a warm spot with indirect light and keep the soil lightly moist. This works especially well in cooler climates where the growing season is short.

3. What happens if I plant ginger too early?
Planting into cold, wet soil can cause rhizomes to rot before they even sprout. Even if they survive, growth will be slow and weak. Waiting until the soil is consistently warm is far more reliable. Consider using a raised bed or container to warm the soil faster.

4. Do different ginger varieties have different planting times?
Culinary ginger (Zingiber officinale) and ornamental types like shampoo ginger (Zingiber zerumbet) both prefer warm soil, but shampoo ginger may tolerate slightly cooler conditions. Always check the specific variety’s hardiness zone. For container growing, our best gardenia small bonsai tree guide offers similar tips for warm-loving plants.

5. How do I know if my soil is warm enough for ginger?
A soil thermometer is the most reliable tool. Insert it 2-3 inches deep in the morning; if the temperature reads at least 68°F for several days in a row, it is safe to plant. Alternatively, wait until nighttime lows stay above 60°F for a week.