Millions of people plant potatoes, and there are millions of ways to do it. Here are some of our favorite tips to give you a robust potato crop in the Mid-Valley region of Oregon.
Pre-sprout Your Potatoes for a Head StartWant to harvest potatoes a month earlier than usual? Get a 4 to 5-week head start when you pre-sprout the seed potatoes before you plant them. In the Pacific Northwest, this is especially effective as it aligns with the region's cooler and moist growing conditions.
The pre-sprouting process typically takes 2 to 3 weeks. Two ways we pre-sprout potatoes:
- Put the potatoes in a single layer in the sun in a warm room (temperature above 60°F). Spread them out so they're not touching. (OR)
- Let them sit in an open paper bag on a window sill.
Once you have sprouts on the potatoes, go ahead and plant them, being mindful of the ideal planting times in the Willamette Valley, which are typically when daytime temperatures range between 50 and 60 degrees Fahrenheit.
Soil Conditions and Fertilization
Do you have access to a nice supply of chicken manure? Save it for another crop. Animal manure, applied alone or as a component of compost, can lead to the potato disease called "scab". Instead, in the Pacific Northwest, focus on enriching the soil with mature compost and maintaining a slightly acidic soil pH, optimal for potato growth.
Considerations for Acidic Soil Conditions
Soil conditions in the Willamette Valley are typically acidic. The region is known for its volcanic soil types, which tend to be naturally acidic. This acidity is beneficial for many crops, including potatoes, which prefer slightly acidic soil conditions. However, soil pH can vary depending on specific locations and management practices, so it's always a good idea for gardeners and farmers to test their soil to determine its exact pH and nutrient levels.
Bone meal is an organic fertilizer that can be beneficial for planting potatoes, including in the Pacific Northwest. It primarily provides phosphorus, essential for healthy root development, and also contains calcium and a small amount of nitrogen. Here's how it can help and recommendations for application:
- Root Development: Phosphorus in bone meal promotes strong root growth, which is crucial for healthy potato development.
- Improves Soil Quality: Bone meal can enhance soil quality over time, especially in areas with poor soil.
- Slow Release: Being a slow-release fertilizer, it provides nutrients over an extended period, beneficial for the entire growing season of potatoes.
- Amount: The general recommendation for bone meal application is about 5 to 10 pounds per 100 square feet. However, this can vary based on the existing soil nutrient levels.
- Application Method: It should be applied at the time of planting. Mix the bone meal into the soil at the bottom of the planting trench or hole before placing the seed potatoes.
- Soil Testing: It's advisable to conduct a soil test prior to application. Since bone meal is high in phosphorus, it's important to ensure your soil needs this nutrient to avoid an imbalance.
Considerations for the Pacific Northwest:
- Rainfall: The Pacific Northwest's high rainfall can leach nutrients from the soil, making the addition of fertilizers like bone meal more important.
Use Straw to Hill Potatoes
Potato tubers need to grow in the dark, and in the Willamette Valley, hilling them up with straw is particularly beneficial. Straw is lightweight and doesn't restrict tuber growth, and it makes for easier harvesting. Plus, there's little dirt to wash off the potatoes. Hill with six inches of straw at planting and each time you see green stems coming up. This method is excellent for maintaining the even moisture levels that potatoes in this region need.
Consistent irrigation is key, especially in the typically dry summers of the Pacific Northwest. Whether you're hilling with soil or straw, use drip irrigation like soaker hoses on timers to supply a regular amount of water. In the Willamette Valley, aim for even, consistent moisture throughout the growing period, supplementing the average rainfall as necessary.
Please let us know your comments and additional tips below. Our staff in Albany are also happy to assist you with your growing questions.