Queen rearing calendar
A queen emerges 16 days after the egg is laid. Enter the day you graft, or the day you confine the breeder queen on a Cupkit or Jenter comb, and get every date of the batch, from the cell builder to the first eggs, ready to add to your calendar.
The batch, day by day
| Day | Date | Stage | What to do |
|---|---|---|---|
| D-17(G-21) | Mon 5 Oct | Drone comb in | Drone comb into your chosen drone colonies, about three weeks before grafting, so drones are mature when the virgins fly. |
| D0(G-4) | Thu 22 Oct | Egg laid | Breeder queen confined on the Cupkit or Jenter comb, or an empty comb put in the breeder colony (or the queen caged on it overnight). |
| D3(G-1) | Sun 25 Oct | Prepare the cell builder | Set up the cell raiser (Cloake board, queenright or queenless) and put the cups in 8 to 24 hours ahead to be polished. |
| D4(G+0) | Mon 26 Oct | Graft or transfer the cups | Larvae 12 to 18 hours after hatching go into the cell builder, the graft frame between pollen and young brood. |
| D5(G+1) | Tue 27 Oct | Acceptance check | Accepted larvae float on a deep bed of royal jelly and the cups are drawn out. Check gently, one to three days after grafting. |
| D8(G+4) | Fri 30 Oct | Cells capped | Queen cells are sealed around day 8. |
| D9 to 14(G+5 to 10) | Sat 31 Oct to Thu 5 Nov | Pupae: do not disturb | No jolting, turning or chilling. In a queenright builder, destroy any emergency cells in the top box six or seven days after grafting. |
| D15(G+11) | Fri 6 Nov | Ripe cells into mating nucs | Eleven days after grafting, one day before emergence (NBU). Tip down, kept warm, next to emerging brood; use an incubator if there is a delay. |
| D16(G+12) | Sat 7 Nov | Virgin queens emerge | A queen takes 16 days from egg to adult. A warm builder can bring emergence forward. |
| D21 to 31(G+17 to 27) | Thu 12 Nov to Sun 22 Nov | Mating flights | Leave the nucs closed in flying weather; a wet British June can delay mating. |
| D29 to 36(G+25 to 32) | Fri 20 Nov to Fri 27 Nov | Check for eggs and mark | The NBU leaves mating nucs alone for about two to three weeks after the cells go in. Look for eggs, then mark the queen in the colour of the year. |
| D38 to 45(G+34 to 41) | Sun 29 Nov to Sun 6 Dec | Sealed worker brood | Judge the laying pattern before selling the queen or introducing her. |
How it is calculated
Everything counts from the egg
A queen develops in 16 days: 3 days as an egg, about 5.5 days as a larva and 7.5 days as a pupa, with the cell sealed around day 8. The calendar takes D0 as the day the egg is laid. A larva 12 to 18 hours after hatching, which hatched on D3, is grafted on D4, so grafting day is G0 = D4.
Grafting: D0 = grafting date − 4 days (− 5 for a two-day-old larva)
Cupkit or Jenter: D0 = day the queen is confined to lay in the cups
date of a stage = D0 + n days| Day from egg | Day from graft | Stage |
|---|---|---|
| D-17 | G-21 | Drone comb in |
| D0 | G-4 | Egg laid |
| D3 | G-1 | Prepare the cell builder |
| D4 | G+0 | Graft or transfer the cups |
| D5 | G+1 | Acceptance check |
| D8 | G+4 | Cells capped |
| D9 to 14 | G+5 | Pupae: do not disturb |
| D15 | G+11 | Ripe cells into mating nucs |
| D16 | G+12 | Virgin queens emerge |
| D21 to 31 | G+17 | Mating flights |
| D29 to 36 | G+25 | Check for eggs and mark |
| D38 to 45 | G+34 | Sealed worker brood |
The acceptance check follows the graft by one to three days. Ripe cells go to mating nucs 11 days after grafting (D15), one day before emergence, as the National Bee Unit does: the first queen out destroys her rivals. With a Cupkit or Jenter comb, the breeder queen is confined for a day or two to lay in the cups, and the larvae are moved on D4 without being touched. Mating and laying depend on the weather: allow two to three weeks from emergence to the first eggs, more in a cold or windy spell.
For the cell builder, the Cloake board, the Miller method and Apidea mating nucs, see our guide to queen rearing; the stages are explained on the honey bee life cycle page. The .ics file opens in Google Calendar, Apple Calendar or Outlook, one all-day event per stage.
Frequently asked questions
How many days from grafting to a queen emerging?
About 12. A queen takes 16 days from egg to adult, and a larva grafted 12 to 18 hours after hatching is already about four days from the egg. The NBU removes the cells 11 days after grafting, one day before emergence, and puts them into mating nucs straight away.
How old should larvae be for grafting?
The NBU grafts worker larvae 12 to 18 hours after hatching, a tiny comma in a pool of brood food. Larvae older than about two days have started to develop as workers and give smaller queens. To get larvae of a known age, put an empty comb in the breeder colony four days before grafting.
How does the Nicot Cupkit work?
The breeder queen is confined in the Cupkit comb box, behind an excluder front, so she lays straight into the removable cell cups. Once the larvae hatch, you move the cups onto the cell bar without touching the larvae. The calendar is the same as for grafting, counted from the day the queen lays in the cups.
When should queen cells go into mating nucs?
Eleven days after grafting, or day 15 from the egg, one day before the first queen emerges. Earlier, the pupae are fragile and easily damaged by a knock or a chill. Later, the first virgin out will tear down the other cells. Keep ripe cells warm and tip down while you move them.
When will a new queen start laying?
Usually two to three weeks after she emerges. A virgin needs about a week to mature, then flying weather for her mating flights, and she starts laying a few days after mating. The NBU leaves mating nucs alone for two to three weeks before checking. A cold, wet spell can delay mating further.
What is the best time of year to rear queens in the UK?
When colonies are strong, drones are flying in numbers and there is a steady flow: in most of England from early or mid May to July. BIBBA gives the end of April to mid August in favourable areas. Scotland and the north usually start a few weeks later, so plan your first graft accordingly.
What colour should I mark a queen this year?
The international code follows the last digit of the year: white for 1 and 6, yellow for 2 and 7, red for 3 and 8, green for 4 and 9, blue for 5 and 0. A queen reared in 2026 is marked white and one reared in 2027 yellow. Mark her once she is laying.
Sources
- Grafting and managing queen cells, Animal and Plant Health Agency, National Bee Unit
- Mating nucs and artificial insemination, Animal and Plant Health Agency, National Bee Unit
- BIBBA guide to forming and running bee improvement groups, Bee Improvement and Bee Breeders’ Association (BIBBA)
- Notes to accompany the record card (2025), Bee Improvement and Bee Breeders’ Association (BIBBA)
- Nicot Cupkit queen rearing system: product description, Simon the Beekeeper
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