Plant lovers truly know no rest! Once your green summer beauties finish blooming, it's time to prepare for the spring bulb garden. Starting early and planting some bulbs in the fall gives you a chance to grow different varieties of plants that require the colder conditions to bloom beautifully in the spring. These early flowering plants will brighten your garden; all it takes is a bit of planning and patience. Continue reading to learn about the ins and outs of how to plant flower bulbs for a lovely summer garden.
When to Plant Bulbs in the Fall and How Late Can We Do It?
The time of planting bulbs is an essential factor when you plan on enjoying some early-spring blooming flowers. You would generally want to plant your bulbs when the temperature drops but before it's freezing outside. The best times to plant your fall bulbs will vary depending on your USDA zone, but there are ways to grow these plants even if you live in a frost-free climate.
Cold Winter Zones
Cold winter zones (USDA Zones 1-7) are regions that typically experience drastic season changes with cold winters. If that's your case, plant bulbs at least 6-8 weeks before the first frost when the ground temperature is between 40-50ºF (4-10˚C) so they can begin to establish themselves in the cool soil before going into a dormant state. However, you can place the bulbs in the ground as long as it isn't frozen and still workable.
Warm Winter Zones
USDA zones 8-11 usually don't get long-lasting freezing temperatures. Therefore, if you live there are plan on planting some bulbs in autumn, you will have to take a few extra steps. The most important is mimicking the coil weather through pre-chilling. The process's duration depends on the plant you pick, but it usually ranges between 11 and 15 weeks. When placing your future green beauty into a refrigerator, avoid storing them near fruits like tomatoes and apples. Then wait for the temperatures to be at their lowest and plant your bulbs in the ground. If you plan on growing the plant in a container, use insulation to mimic the temperature of the ground.
What Bulbs Should We Plant in October?
Irises, alliums, hyacinths, and tulips are suitable bulbs to plant in the fall, starting in early to late October, depending on where you are in the cold winter zone. Any fall bulb is ready to plant in October if the ground temperature is between 40-50ºF (4-10˚C).
Best Bulbs to Plant in the Fall
There are a ton of options available for fall bulb planting. If you are new to this, the variety might feel overwhelming. To make things easier for you, we have already prepared an article on ‘Best Bulbs to Plant in Fall’. Check it out to pick the best option for you!
There is also another useful trick, charts. They are beneficial for planning your spring garden using fall bulbs. Use this chart to check all the needed information, including light and zone preferences, planting time, soil type, and planting depth. We also included spacing information to ensure that all your green pets get their personal bubble.
How to Plant Bulbs in Fall
Planting bulbs is fairly similar in all seasons. However, there are some extra steps you need to take when working in the fall. Most bulbs are perennials, too, so you can count on enjoying them for seasons to come.
- Planting flower bulbs begins with some pre-work organization. Since you won't see these plants until they flower, it's important to know what you have and where it is. Keep your plants labeled if you'd like to know what's going on beneath the soil.
- Pick an area for planting. Consult your flower's label or grower's chart to decide where to place your bulbs and how much sunlight or shade they need to perform their best. Avoid areas where water tends to pool up, such as at the bottom of hills. Excess moisture can quickly rot your bulbs.
- Prepare the soil. Work the soil to loosen it before planting the bulbs. The planting depth is usually specified on the label, so ensure to work enough of the soil to plant your future green beauty appropriately. If needed, now would be the time to amend the soil. Add any compost or slow-release fertilizer if you find the soil to be of poor quality.
- Plant your bulbs. After preparing and amending the soil, you can begin planting! Ensure you space out your bulbs appropriately and plant at the necessary depth so the green pets can go through all their growth stages effectively for blooming in the spring. Try your best to plant your bulbs facing up. Usually, this is the pointed side of the bulb that should be facing upwards. If you're unsure, simply place them in a neutral position (like on their side), and thanks to gravity, they will find their way up. Cover the bulbs back up with soil and gently pack it down. Don't pack the soil too hard because then the shoots will have a hard time emerging.
- Provide enough water. Water your bulbs well after planting to help them get established in the soil. From here, watering isn't necessary unless you live in a warm, dry climate that doesn't get much rain during the fall or winter months.
Other Plants’ Bulbs
You can use the above steps for planting other bulbs, such as alliums. Place your alliums at 3-6 inches (7-14 cm) depth and give them at least 6 inches (14 cm) of space between the bulbs.
As always, pay attention to the label and consult growing charts as needed to ensure you're giving your bulbs the best chance of success possible.
How Deep to Plant Bulbs
The depth to plant bulbs will often vary on the type and size of the plant. Usually, you should be able to find the recommendations on your green pet's label or bag. A good rule of thumb is to plant large bulbs (usually at least 4.5 inches/12cm) at a depth of 8 inches (20 cm) in the ground. Smaller bulbs can be planted a bit more shallow, at around 5 inches (12 cm).
These recommendations are crucial, and you shouldn't overlook them. Planting too deep can prevent your bulbs from growing shoots from breaking through the spring soil. Shallow planting may allow animals to dig out the bulbs. Both of these situations will likely lead to a complete lack of flowering and potentially destroy the bulb entirely.
There are some general steps and requirements for fall bulb planting. However, you can pick your own method of planting. Look through the following options to choose the one that suits your garden best!
- Mass planting. This method will yield a colorful array of bulbs. It consists of planting many bulbs in one area while providing the needed space for each one. There isn't necessarily a row or pattern established with this method.
- Individual planting. It is common to plant bulbs in the garden, especially in small spaces. If you wish to go with individual planting, simply dig separate holes in whatever arrangement you desire.
- Border or Trench planting. You can arrange bulbs to form borders anywhere you'd like and give an orderly appearance to your garden. Dig out trenches where you'd like your bulbs to grow at the appropriate depth.
- Bouquet planting. A more whimsical method, bouquet planting, consists of digging a large hole that is wide enough for the desired amount of bulbs to be planted together. Here, spacing isn't much of a concern. Ensure the bulbs aren't touching each other. When they bloom, they appear to be an expertly arranged bouquet of spring-blooming bulbs.
- Container planting. This method is perfect for small-space gardeners or gardeners who do not have a permanent garden. Ensure your pot is deep enough for the size of the bulb you are planting, and consider insulating these containers by either planting them in the ground or using straw or horticultural fleece. They will help keep your bulbs at the right temperature for growth and development.
Proper Bulb Planting in the Fall
Going through all the steps in planting your bulbs may still yield less than stellar results if you overlook the integral steps. Here are some tips that you shouldn't skip when planting fall bulbs:
- Pay attention to the light. Planting bulbs does require some foresight since you won't be seeing the plants emerge for a few months. Know your plant's requirements and how much light they'll need to get once they breach the soil.
- Provide the correct amount of water. Besides the initial watering after planting, most fall bulbs do not require much water besides regular rainfall. If you're in a warmer zone (8-11), then you may need to water once or twice, depending on how warm of a season you're having, but it may not be necessary if the bulbs have been refrigerated then planted during the coolest part of the year.
- Be cautious of the temperature. Fall bulbs are fall specific for a reason. Overly warm and wet soils can cause your bulbs to rot before they get a chance to grow. The cool soil temperature gives your plants some time to get established and develop roots before they go dormant for the winter. Warming soil in the spring will signal to your green pet that it's time to grow.
- Pay attention to the depth of planting. Follow the suggested depth requirements for planting as closely as possible. Many bulbs grow robust root systems, and planting at the right depth will give them the highest chance of successful blooms and longevity throughout the seasons.
Do we need to water bulbs planted in the fall?
Aside from the initial watering after planting, excess water usually isn't necessary, especially in the cooler zones. If you live in warm or drought-prone areas, bulbs may need additional watering once or twice before they emerge from the soil.
Do we soak bulbs before planting in the fall?
Fall bulbs need no previous soaking to be successful in the spring. Excess water or planting the bulbs while the soil is warm and wet can do more harm than good and lead to rot, destroying the chance of that bulb contributing to your spring garden.
How to prepare bulbs for fall planting?
We suggest buying the bulbs close to the planned planting date. This trick will help you get the freshest and healthiest bulbs possible. Old or cheap bulbs may not bloom as well as fresh ones, and since they can last for years, it is better to get the best option available. If you need to store your bulbs before planting, do so in the fridge, but keep them away from fruits that give off gasses. These gasses can inhibit blooming in your bulb, making planting pointless.
When is the best time to plant bulbs?
Fall bulbs (bulbs that bloom in the spring) should be planted well before the first frost, at least 6-8 weeks before this, to get established in the soil before it gets too cold. Bulbs planted in the spring for summer blooming are best planted after the last frost, usually in March or April, depending on your zone.