Johnsons Shirley F1 Tomato Seeds
Not Available
Not Available
Currently unavailable
Currently out of stock
This product is not available at the moment. Check back later or explore other options below.
Product Information
Full details
Johnsons Shirley F1 Tomato Seeds are an ideal choice for both novice and experienced greenhouse gardeners seeking a reliable, high-yield variety. These seeds are prized for their ability to produce large trusses of medium-sized fruit early in the season, though they require dedicated space and support structures as indeterminate vining plants.
All features
| Brand | Johnsons Seeds |
|---|
Extended Product Information
FAQs
When is the best time to sow Shirley F1 seeds?
For the best results, sow your seeds indoors between January and March.
Can I grow these outside?
While intended primarily as a greenhouse variety, they can be grown outdoors in a very sheltered, sunny spot, but yield and ripening times may be affected.
Do I need to prune these tomatoes?
Yes, as an indeterminate variety, you should regularly pinch out side shoots to maintain a single main stem.
How long until I can harvest?
Under normal greenhouse conditions, you can expect to harvest your tomatoes from June through October.
What is greenback resistance?
Greenback is a physiological disorder where the top of the tomato remains green and hard; this variety is bred to resist this issue, ensuring uniform ripening.
Troubleshooting
Flowers are falling off before fruit forms
This is often caused by poor pollination or temperature stress; gently shake the plant stems to distribute pollen or improve greenhouse ventilation.
Fruit splitting or cracking
Usually the result of inconsistent watering; aim to keep the soil moisture levels steady rather than letting them fluctuate between very dry and soaked.
Plant looks spindly or 'leggy'
This indicates a lack of sufficient light; move seedlings closer to a window or increase the duration of grow light exposure.
Pros and Cons
Pros
- Early ripening period allows for a long harvest window
- High resistance to common greenhouse issues like leaf mould
- Consistently produces large, high-quality fruit trusses
- Verified performance with RHS Award of Garden Merit
Cons
- Requires greenhouse environment for best results
- Needs physical support, such as canes or strings, due to vining nature
- Indeterminate growth requires regular pruning of side shoots
Setup, Compatibility & Care
To ensure a successful crop, maintain a steady temperature in your greenhouse. Consistent watering is essential, especially once the first trusses begin to form, to prevent fruit splitting. Feed the plants with a high-potash tomato fertilizer once the first fruits start to set to encourage continuous production. Regularly pinch out the 'side shoots'—the small growths appearing in the leaf axils—to direct the plant's energy into fruit production rather than excess foliage. Keep the greenhouse well-ventilated during hot summer days to discourage fungal issues, despite the variety's inherent resistance.