Unusual warmth in Finland disrupts autumn gardening practices

This autumn in Finland has been unusually warm, with many weather stations recording average temperatures about four to six degrees Celsius above normal around mid-September. This warmth has persisted into the end of the month, aided by the sea’s influence on the Helsinki metropolitan area. A temperature wave near the Gulf of Finland has lasted almost 50 days, starting in early August.

Biologist Leena Luoto warns that the unseasonably warm weather is misleading plants, preventing them from properly preparing for winter. She provides three key tips for home gardeners during this period:

1. Conduct a Spade Test: Gardeners in Southern Finland can still plant container-grown seedlings. To check if the soil is adequately moist, Luoto recommends using a spade to dig a chunk of soil down to the blade’s depth. If the soil is overly dry, the plants may struggle to root. During May to August, rainfall has been minimal, and recent heavy rains have not sufficiently hydrated the ground. A good rule of thumb is that 10 millimeters of rain equals one watering can per square meter. It’s essential to water the planting hole thoroughly and spread the roots of the seedling.

2. Plant Crocuses Soon: Crocus bulbs should be planted now, while tulip bulbs can wait for the soil to cool. Luoto emphasizes that tulip bulbs, when planted in warm soil, could rot rather than sprout, making a cooler soil temperature necessary for root development.

3. Avoid Excessive Protection: While some plants are preparing for winter, others are not recognizing the end of summer. Luoto advises protecting young fruit trees and ornamental shrubs from deer and rabbits with nets. However, covering plants too soon can be detrimental, as moisture and warmth combined can be harmful. She highlights the diverse conditions across Finland; local weather should be monitored closely, keeping in mind that frost can already be a concern in some areas.